U.S. patent application number 17/646191 was filed with the patent office on 2022-05-12 for enabling application access to cloud data.
The applicant listed for this patent is Snowflake, Inc.. Invention is credited to Christopher Peter Child, Matthew J. Glickman, Justin Langseth.
Application Number | 20220147647 17/646191 |
Document ID | / |
Family ID | |
Filed Date | 2022-05-12 |
United States Patent
Application |
20220147647 |
Kind Code |
A1 |
Child; Christopher Peter ;
et al. |
May 12, 2022 |
ENABLING APPLICATION ACCESS TO CLOUD DATA
Abstract
Security credentials associated with a first account maintained
by a database system are authenticated. Based on authenticating the
security credentials, a user interface element is provided to
enable sharing of customer data associated with the first account
with an application. A request to share customer data with the
application is received. Based on the request, third-party data
that is accessible by the first account is identified. The
third-party data corresponds to a second account maintained by the
database system. The second account corresponds to a third-party
data provider. The application is enabled to access cloud data
associated with the first account based on the request. The cloud
data comprises the customer data and the third-party data.
Inventors: |
Child; Christopher Peter;
(Tiburon, CA) ; Glickman; Matthew J.; (Larchmont,
NY) ; Langseth; Justin; (Kailua, HI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Snowflake, Inc. |
Bozeman |
MT |
US |
|
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Appl. No.: |
17/646191 |
Filed: |
December 28, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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17162376 |
Jan 29, 2021 |
11244067 |
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17646191 |
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63112831 |
Nov 12, 2020 |
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International
Class: |
G06F 21/62 20060101
G06F021/62; G06F 16/248 20060101 G06F016/248; G06F 16/2457 20060101
G06F016/2457; G06F 16/28 20060101 G06F016/28; G06F 21/31 20060101
G06F021/31; G06F 3/06 20060101 G06F003/06 |
Claims
1. A database system comprising: at least one hardware processor;
and at least one memory storing instructions that cause the at
least one hardware processor to perform operations comprising:
receiving a request specifying cloud data to share with an
application and indicating one or more limitations on use of the
cloud data by the application, the cloud data including customer
data associated with an account maintained by the database system;
based on the request, verifying compatibility of cloud data with
the application by performing one or more validations of the cloud
data, the performing of the one or more validations comprising
validating a schema of the cloud data; performing, based on the
request, one or more normalization operations on the cloud data;
and based on verifying compatibility of the cloud data with the
application and performing the one or more normalization
operations, enabling the application to access the cloud data based
on the request, the enabling of the application to access the cloud
data comprising restricting use of the cloud data by the
application according to the one or more limitations indicated in
the request.
2. The database system of claim 1, wherein: the account is a first
account; the operations further comprise identifying third-party
data that is accessible by the first account, the third-party data
corresponding to a second account maintained by the database
system, the second account corresponding to a third-party data
provider; and the cloud data further includes the third-party
data.
3. The database system of claim 2, wherein enabling the application
to access the cloud data includes enabling the application to
access the third-party data based on an indication in the request
to share the third-party data with the application.
4. The database system of claim 1, wherein: the application is a
first application; the operations further comprise identifying
second-party application data to which the account is granted
access, the second-party application data comprising application
data corresponding to a second application provided by a
second-party application provider; and the cloud data further
comprises the second-party application data.
5. The database system of claim 4, wherein enabling the first
application to access the cloud data includes enabling the first
application to access the second-party application data based on an
indication in the request to share the second-party application
data with the first application.
6. The database system of claim 1, wherein the one or more
limitations include a limitation that restricts access to a
specific portion of the cloud data.
7. The database system of claim 1, wherein the one or more
limitations specify read or write permissions associated with one
or more portions of the cloud data.
8. The database system of claim 1, wherein: the request is received
from a computing device executing the application.
9. The database system of claim 8, wherein: the operations further
comprise providing a first user interface element to the computing
device to enable sharing of the cloud data with the application;
and the requests is generated based on interaction with the first
user interface element.
10. The database system of claim 9, wherein: the operations further
comprise: providing, to the application, a second user interface
element to receive security credentials associated with the
account, the application causing the computing device to present
the second user interface element; and receiving an authentication
request generated based on user interaction with the second user
interface element, the authentication request comprising the
security credentials; and the first user interface element is
provided in response to receiving the authentication request.
11. A method comprising: receiving a request specifying cloud data
to share with an application and indicating one or more limitations
on use of the cloud data by the application, the cloud data
including customer data associated with an account maintained by a
database system; based on the request, verifying, by one or more
hardware processors of a machine, compatibility of cloud data with
the application by performing one or more validations of the cloud
data, the performing of the one or more validations comprising
validating a schema of the cloud data; performing, by the one or
more hardware processors of the machine, one or more normalization
operations on the cloud data; and based on verifying compatibility
of the cloud data with the application and performing the one or
more normalization operations, enabling the application to access
the cloud data based on the request, the enabling of the
application to access the cloud data comprising restricting use of
the cloud data by the application according to the one or more
limitations indicated in the request.
12. The method of claim 11, wherein: the account is a first
account; the method further comprises identifying third-party data
that is accessible by the first account, the third-party data
corresponding to a second account maintained by the database
system, the second account corresponding to a third-party data
provider; and the cloud data further includes the third-party
data.
13. The method of claim 12, wherein enabling the application to
access the cloud data includes enabling the application to access
the third-party data based on an indication in the request to share
the third-party data with the application.
14. The method of claim 11, wherein: the application is a first
application; the method further comprises identifying second-party
application data to which the account is granted access, the
second-party application data comprising application data
corresponding to a second application provided by a second-party
application provider; and the cloud data further comprises the
second-party application data.
15. The method of claim 14, wherein enabling the first application
to access the cloud data includes enabling the first application to
access the second-party application data based on an indication in
the request to share the second-party application data with the
first application.
16. The method of claim 11, wherein the one or more limitations
include a limitation that restricts access to a specific portion of
the cloud data.
17. The method of claim 11, wherein the one or more limitations
specify read or write permissions associated with one or more
portions of the cloud data.
18. The method of claim 11, wherein: the request is received from a
computing device executing the application.
19. The method of claim 18, wherein: the method further comprises
providing a first user interface element to the computing device to
enable sharing of the cloud data with the application; and the
requests is generated based on interaction with the first user
interface element.
20. The method of claim 19, further comprising: providing, to the
application, a second user interface element to receive security
credentials associated with the account, the application causing
the computing device to present the second user interface element;
and receiving an authentication request generated based on user
interaction with the second user interface element, the
authentication request comprising the security credentials; and the
first user interface element is provided in response to receiving
the authentication request.
21. A non-transitory computer-storage medium storing instructions
that cause at least one hardware processor to perform operations
comprising: receiving a request specifying cloud data to share with
an application and indicating one or more limitations on use of the
cloud data by the application, the cloud data including customer
data associated with an account maintained by a database system;
based on the request, verifying compatibility of cloud data with
the application by performing one or more validations of the cloud
data, the performing of the one or more validations comprising
validating a schema of the cloud data; performing, based on the
request, one or more normalization operations on the cloud data;
and based on verifying compatibility of the cloud data with the
application and performing the one or more normalization
operations, enabling the application to access the cloud data based
on the request, the enabling of the application to access the cloud
data comprising restricting use of the cloud data by the
application according to the one or more limitations indicated in
the request.
22. The non-transitory computer-storage medium of claim 21,
wherein: the account is a first account; the operations further
comprise identifying third-party data that is accessible by the
first account, the third-party data corresponding to a second
account maintained by the database system, the second account
corresponding to a third-party data provider; and the cloud data
further includes the third-party data.
23. The non-transitory computer-storage medium of claim 22, wherein
enabling the application to access the cloud data includes enabling
the application to access the third-party data based on an
indication in the request to share the third-party data with the
application.
24. The non-transitory computer-storage medium of claim 21,
wherein: the application is a first application; the operations
further comprise identifying second-party application data to which
the account is granted access, the second-party application data
comprising application data corresponding to a second application
provided by a second-party application provider; and the cloud data
further comprises the second-party application data.
25. The non-transitory computer-storage medium of claim 24,
wherein: wherein enabling the first application to access the cloud
data includes enabling the first application to access the
second-party application data based on an indication in the request
to share the second-party application data with the first
application.
26. The non-transitory computer-storage medium of claim 21, wherein
the one or more limitations include a limitation that restricts
access to a specific portion of the cloud data.
27. The non-transitory computer-storage medium of claim 21, wherein
the one or more limitations specify read or write permissions
associated with one or more portions of the cloud data.
28. The non-transitory computer-storage medium of claim 21,
wherein: the request is received from a computing device executing
the application.
29. The non-transitory computer-storage medium of claim 28,
wherein: the operations further comprise providing a first user
interface element to the computing device to enable sharing of the
cloud data with the application; and the requests is generated
based on interaction with the first user interface element.
30. The non-transitory computer-storage medium of claim 29,
wherein: the operations further comprise: providing, to the
application, a second user interface element to receive security
credentials associated with the account, the application causing
the computing device to present the second user interface element;
and receiving an authentication request generated based on user
interaction with the second user interface element, the
authentication request comprising the security credentials; and the
first user interface element is provided in response to receiving
the authentication request.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of U.S. patent
application Ser. No. 17/162,376 filed Jan. 29, 2021, which claims
priority to U.S. Provisional Patent Application Ser. No.
63/112,931, filed on Nov. 12, 2020, the contents of which are
incorporated by reference in their entireties.
TECHNICAL FIELD
[0002] Embodiments of the disclosure relate generally to databases
and, more specifically, to enabling applications to access data in
a database system.
BACKGROUND
[0003] Databases are widely used for data storage and access in
computing applications. A goal of database storage is to provide
enormous sums of information in an organized manner so that it can
be accessed, managed, updated, and shared. In a database, data may
be organized into rows, columns, and tables. Databases are used by
various entities and companies for storing information that may
need to be accessed or analyzed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The present disclosure will be understood more fully from
the detailed description given below and from the accompanying
drawings of various embodiments of the disclosure.
[0005] FIG. 1 illustrates an example computing environment that
includes a network-based database system in communication with a
cloud storage provider system, in accordance with some embodiments
of the present disclosure.
[0006] FIG. 2 is a block diagram illustrating components of a
compute service manager, in accordance with some embodiments of the
present disclosure.
[0007] FIG. 3 is a block diagram illustrating components of an
execution platform, in accordance with some embodiments of the
present disclosure.
[0008] FIGS. 4A and 4B illustrates an example computing environment
in which an application is connected to a database system, in
accordance with some embodiments of the present disclosure
[0009] FIG. 5 illustrates an example architecture to support
applications with connections to a database system, in accordance
with some embodiments of the present disclosure.
[0010] FIGS. 6 and 7 are flow diagrams illustrating operations of
the database system in performing a method for connecting an
application to a database system, in accordance with some
embodiments of the present disclosure.
[0011] FIG. 8 illustrates a diagrammatic representation of a
machine in the form of a computer system within which a set of
instructions may be executed for causing the machine to perform any
one or more of the methodologies discussed herein, in accordance
with some embodiments of the present disclosure.
DETAILED DESCRIPTION
[0012] Reference will now be made in detail to specific example
embodiments for carrying out the inventive subject matter. Examples
of these specific embodiments are illustrated in the accompanying
drawings, and specific details are set forth in the following
description in order to provide a thorough understanding of the
subject matter. It will be understood that these examples are not
intended to limit the scope of the claims to the illustrated
embodiments. On the contrary, they are intended to cover such
alternatives, modifications, and equivalents as may be included
within the scope of the disclosure.
[0013] Aspects of the present disclosure address a multi-tenant
database system that supports sharing of user data with a
multi-tenant application. The application includes a user interface
that exposes an element that allows a user of the application to
incorporate their data cloud assets (including first, second,
third-party assets) into the application context to enrich the
experience. Once the connection is established, the application can
use specified data for a specified context and can also add more
data to the user's data graph.
[0014] FIG. 1 illustrates an example computing environment 100 that
includes a database system 102 in communication with a storage
platform 104, in accordance with some embodiments of the present
disclosure. To avoid obscuring the inventive subject matter with
unnecessary detail, various functional components that are not
germane to conveying an understanding of the inventive subject
matter have been omitted from FIG. 1. However, a skilled artisan
will readily recognize that various additional functional
components may be included as part of the computing environment 100
to facilitate additional functionality that is not specifically
described herein.
[0015] As shown, the computing environment 100 comprises the
database system 102 and a storage platform 104 (e.g., AWS.RTM.,
Microsoft Azure Blob Storage.RTM., or Google Cloud Storage.RTM.).
The database system 102 is used for reporting and analysis of
integrated data from one or more disparate sources including
storage devices 106-1 to 106-N within the storage platform 104. The
storage platform 104 comprises a plurality of computing machines
and provides on-demand computer system resources such as data
storage and computing power to the database system 102.
[0016] The database system 102 comprises a compute service manager
108, an execution platform 110, and a database 114. The database
system 102 hosts and provides data reporting and analysis services
to multiple client accounts. Administrative users can create and
manage identities (e.g., users, roles, and groups) and use
permissions to allow or deny access to the identities to resources
and services.
[0017] The compute service manager 108 coordinates and manages
operations of the database system 102. The compute service manager
108 also performs query optimization and compilation as well as
managing clusters of computing services that provide compute
resources (also referred to as "virtual warehouses"). The compute
service manager 108 can support any number of client accounts, such
as end users providing data storage and retrieval requests, system
administrators managing the systems and methods described herein,
and other components/devices that interact with compute service
manager 108.
[0018] The compute service manager 108 is also in communication
with a computing device 112. The computing device 112 corresponds
to a user of one of the multiple client accounts supported by the
database system 102. In some embodiments, the compute service
manager 108 does not receive any direct communications from the
computing device 112 and only receives communications concerning
jobs from a queue within the database system 102.
[0019] The compute service manager 108 is also coupled to database
114, which is associated with the data stored in the computing
environment 100. The database 114 stores data pertaining to various
functions and aspects associated with the database system 102 and
its users. In some embodiments, the database 114 includes a summary
of data stored in remote data storage systems as well as data
available from a local cache. Additionally, the database 114 may
include information regarding how data is organized in remote data
storage systems (e.g., the storage platform 104) and the local
caches. The database 114 allows systems and services to determine
whether a piece of data needs to be accessed without loading or
accessing the actual data from a storage device.
[0020] The compute service manager 108 is further coupled to the
execution platform 110, which provides multiple computing resources
that execute various data storage and data retrieval tasks. The
execution platform 110 is coupled to storage platform 104. The
storage platform 104 comprises multiple data storage devices 106-1
to 106-N. In some embodiments, the data storage devices 106-1 to
106-N are cloud-based storage devices located in one or more
geographic locations. For example, the data storage devices 106-1
to 106-N may be part of a public cloud infrastructure or a private
cloud infrastructure. The data storage devices 106-1 to 106-N may
be hard disk drives (HDDs), solid state drives (SSDs), storage
clusters, Amazon S3.TM. storage systems, or any other data storage
technology. Additionally, the storage platform 104 may include
distributed file systems (e.g., Hadoop Distributed File Systems
(HDFS)), object storage systems, and the like.
[0021] The execution platform 110 comprises a plurality of compute
nodes. A set of processes on a compute node executes a query plan
compiled by the compute service manager 108. The set of processes
can include: a first process to execute the query plan; a second
process to monitor and delete database partition files using a
least recently used (LRU) policy and implement an out of memory
(00M) error mitigation process; a third process that extracts
health information from process logs and status to send back to the
compute service manager 108; a fourth process to establish
communication with the compute service manager 108 after a system
boot; and a fifth process to handle all communication with a
compute cluster for a given job provided by the compute service
manager 108 and to communicate information back to the compute
service manager 108 and other compute nodes of the execution
platform 110.
[0022] In some embodiments, communication links between elements of
the computing environment 100 are implemented via one or more data
communication networks. These data communication networks may
utilize any communication protocol and any type of communication
medium. In some embodiments, the data communication networks are a
combination of two or more data communication networks (or
sub-networks) coupled to one another. In alternate embodiments,
these communication links are implemented using any type of
communication medium and any communication protocol.
[0023] As shown in FIG. 1, the data storage devices 106-1 to 106-N
are decoupled from the computing resources associated with the
execution platform 110. This architecture supports dynamic changes
to the database system 102 based on the changing data
storage/retrieval needs as well as the changing needs of the users
and systems. The support of dynamic changes allows the database
system 102 to scale quickly in response to changing demands on the
systems and components within the database system 102. The
decoupling of the computing resources from the data storage devices
supports the storage of large amounts of data without requiring a
corresponding large amount of computing resources. Similarly, this
decoupling of resources supports a significant increase in the
computing resources utilized at a particular time without requiring
a corresponding increase in the available data storage
resources.
[0024] The compute service manager 108, database 114, execution
platform 110, and storage platform 104 are shown in FIG. 1 as
individual discrete components. However, each of the compute
service manager 108, database 114, execution platform 110, and
storage platform 104 may be implemented as a distributed system
(e.g., distributed across multiple systems/platforms at multiple
geographic locations). Additionally, each of the compute service
manager 108, database 114, execution platform 110, and storage
platform 104 can be scaled up or down (independently of one
another) depending on changes to the requests received and the
changing needs of the database system 102. Thus, in the described
embodiments, the database system 102 is dynamic and supports
regular changes to meet the current data processing needs.
[0025] During typical operation, the database system 102 processes
multiple jobs determined by the compute service manager 108. These
jobs are scheduled and managed by the compute service manager 108
to determine when and how to execute the job. For example, the
compute service manager 108 may divide the job into multiple
discrete tasks and may determine what data is needed to execute
each of the multiple discrete tasks. The compute service manager
108 may assign each of the multiple discrete tasks to one or more
nodes of the execution platform 110 to process the task. The
compute service manager 108 may determine what data is needed to
process a task and further determine which nodes within the
execution platform 110 are best suited to process the task. Some
nodes may have already cached the data needed to process the task
and, therefore, be a good candidate for processing the task.
Metadata stored in the database 114 assists the compute service
manager 108 in determining which nodes in the execution platform
110 have already cached at least a portion of the data needed to
process the task. One or more nodes in the execution platform 110
process the task using data cached by the nodes and, if necessary,
data retrieved from the storage platform 104. It is desirable to
retrieve as much data as possible from caches within the execution
platform 110 because the retrieval speed is typically much faster
than retrieving data from the storage platform 104.
[0026] As shown in FIG. 1, the computing environment 100 separates
the execution platform 110 from the storage platform 104. In this
arrangement, the processing resources and cache resources in the
execution platform 110 operate independently of the data storage
devices 106-1 to 106-N in the storage platform 104. Thus, the
computing resources and cache resources are not restricted to
specific data storage devices 106-1 to 106-N. Instead, all
computing resources and all cache resources may retrieve data from,
and store data to, any of the data storage resources in the storage
platform 104.
[0027] FIG. 2 is a block diagram illustrating components of the
compute service manager 108, in accordance with some embodiments of
the present disclosure. As shown in FIG. 2, the compute service
manager 108 includes an access manager 202 and a key manager 204
coupled to a data storage device 206. Access manager 202 handles
authentication and authorization tasks for the systems described
herein. Key manager 204 manages storage and authentication of keys
used during authentication and authorization tasks. For example,
access manager 202 and key manager 204 manage the keys used to
access data stored in remote storage devices (e.g., data storage
devices in storage platform 104). As used herein, the remote
storage devices may also be referred to as "persistent storage
devices" or "shared storage devices."
[0028] A request processing service 208 manages received data
storage requests and data retrieval requests (e.g., jobs to be
performed on database data). For example, the request processing
service 208 may determine the data necessary to process a received
query (e.g., a data storage request or data retrieval request). The
data may be stored in a cache within the execution platform 110 or
in a data storage device in storage platform 104.
[0029] A management console service 210 supports access to various
systems and processes by administrators and other system managers.
Additionally, the management console service 210 may receive a
request to execute a job and monitor the workload on the
system.
[0030] The compute service manager 108 also includes a job compiler
212, a job optimizer 214 and a job executor 216. The job compiler
212 parses a job into multiple discrete tasks and generates the
execution code for each of the multiple discrete tasks. The job
optimizer 214 determines the best method to execute the multiple
discrete tasks based on the data that needs to be processed. The
job optimizer 214 also handles various data pruning operations and
other data optimization techniques to improve the speed and
efficiency of executing the job. The job executor 216 executes the
execution code for jobs received from a queue or determined by the
compute service manager 108.
[0031] A job scheduler and coordinator 218 sends received jobs to
the appropriate services or systems for compilation, optimization,
and dispatch to the execution platform 110. For example, jobs may
be prioritized and processed in that prioritized order. In an
embodiment, the job scheduler and coordinator 218 determines a
priority for internal jobs that are scheduled by the compute
service manager 108 with other "outside" jobs such as user queries
that may be scheduled by other systems in the database but may
utilize the same processing resources in the execution platform
110. In some embodiments, the job scheduler and coordinator 218
identifies or assigns particular nodes in the execution platform
110 to process particular tasks. A virtual warehouse manager 220
manages the operation of multiple virtual warehouses implemented in
the execution platform 110. As discussed below, each virtual
warehouse includes multiple execution nodes that each include a
cache and a processor.
[0032] Additionally, the compute service manager 108 includes a
configuration and metadata manager 222, which manages the
information related to the data stored in the remote data storage
devices and in the local caches (e.g., the caches in execution
platform 110). The configuration and metadata manager 222 uses the
metadata to determine which partitions need to be accessed to
retrieve data for processing a particular task or job. A monitor
and workload analyzer 224 oversees processes performed by the
compute service manager 108 and manages the distribution of tasks
(e.g., workload) across the virtual warehouses and execution nodes
in the execution platform 110. The monitor and workload analyzer
224 also redistributes tasks, as needed, based on changing
workloads throughout the database system 102 and may further
redistribute tasks based on a user (e.g., "external") query
workload. The execution platform 110 may also redistribute tasks
based on a user (e.g., "external") query workload. The
configuration and metadata manager 222 and the monitor and workload
analyzer 224 are coupled to a data storage device 226. Data storage
device 226 in FIG. 2 represents any data storage device within the
database system 102. For example, data storage device 226 may
represent caches in execution platform 110, storage devices in
storage platform 104, or any other storage device.
[0033] FIG. 3 is a block diagram illustrating components of the
execution platform 110, in accordance with some embodiments of the
present disclosure. As shown in FIG. 3, the execution platform 110
includes multiple virtual warehouses, including virtual warehouse
1, virtual warehouse 2, and virtual warehouse n. Each virtual
warehouse includes multiple execution nodes that each includes a
data cache and a processor. The virtual warehouses can execute
multiple tasks in parallel by using the multiple execution nodes.
As discussed herein, the execution platform 110 can add new virtual
warehouses and drop existing virtual warehouses in real-time based
on the current processing needs of the systems and users. This
flexibility allows the execution platform 110 to quickly deploy
large amounts of computing resources when needed without being
forced to continue paying for those computing resources when they
are no longer needed. All virtual warehouses can access data from
any data storage device (e.g., any storage device in storage
platform 104).
[0034] Although each virtual warehouse shown in FIG. 3 includes
three execution nodes, a particular virtual warehouse may include
any number of execution nodes. Further, the number of execution
nodes in a virtual warehouse is dynamic, such that new execution
nodes are created when additional demand is present, and existing
execution nodes are deleted when they are no longer necessary.
[0035] Each virtual warehouse is capable of accessing any of the
data storage devices 106-1 to 106-N shown in FIG. 1. Thus, the
virtual warehouses are not necessarily assigned to a specific data
storage device 106-1 to 106-n and, instead, can access data from
any of the data storage devices 106-1 to 106-N within the storage
platform 104. Similarly, each of the execution nodes shown in FIG.
3 can access data from any of the data storage devices 106-1 to
106-N. In some embodiments, a particular virtual warehouse or a
particular execution node may be temporarily assigned to a specific
data storage device, but the virtual warehouse or execution node
may later access data from any other data storage device.
[0036] In the example of FIG. 3, virtual warehouse 1 includes three
execution nodes 302-1, 302-2, and 302-n. Execution node 302-1
includes a cache 304-1 and a processor 306-1. Execution node 302-2
includes a cache 304-2 and a processor 306-2. Execution node 302-n
includes a cache 304-n and a processor 306-n. Each execution node
302-1, 302-2, and 302-n is associated with processing one or more
data storage and/or data retrieval tasks. For example, a virtual
warehouse may handle data storage and data retrieval tasks
associated with an internal service, such as a clustering service,
a materialized view refresh service, a file compaction service, a
storage procedure service, or a file upgrade service. In other
implementations, a particular virtual warehouse may handle data
storage and data retrieval tasks associated with a particular data
storage system or a particular category of data.
[0037] Similar to virtual warehouse 1 discussed above, virtual
warehouse 2 includes three execution nodes 312-1, 312-2, and 312-n.
Execution node 312-1 includes a cache 314-1 and a processor 316-1.
Execution node 312-2 includes a cache 314-2 and a processor 316-2.
Execution node 312-n includes a cache 314-n and a processor 316-n.
Additionally, virtual warehouse 3 includes three execution nodes
322-1, 322-2, and 322-n. Execution node 322-1 includes a cache
324-1 and a processor 326-1. Execution node 322-2 includes a cache
324-2 and a processor 326-2. Execution node 322-n includes a cache
324-n and a processor 326-n.
[0038] In some embodiments, the execution nodes shown in FIG. 3 are
stateless with respect to the data the execution nodes are caching.
For example, these execution nodes do not store or otherwise
maintain state information about the execution node or the data
being cached by a particular execution node. Thus, in the event of
an execution node failure, the failed node can be transparently
replaced by another node. Since there is no state information
associated with the failed execution node, the new (replacement)
execution node can easily replace the failed node without concern
for recreating a particular state.
[0039] Although the execution nodes shown in FIG. 3 each includes
one data cache and one processor, alternate embodiments may include
execution nodes containing any number of processors and any number
of caches. Additionally, the caches may vary in size among the
different execution nodes. The caches shown in FIG. 3 store, in the
local execution node, data that was retrieved from one or more data
storage devices in storage platform 104. Thus, the caches reduce or
eliminate the bottleneck problems occurring in platforms that
consistently retrieve data from remote storage systems. Instead of
repeatedly accessing data from the remote storage devices, the
systems and methods described herein access data from the caches in
the execution nodes, which is significantly faster and avoids the
bottleneck problem discussed above. In some embodiments, the caches
are implemented using high-speed memory devices that provide fast
access to the cached data. Each cache can store data from any of
the storage devices in the storage platform 104.
[0040] Further, the cache resources and computing resources may
vary between different execution nodes. For example, one execution
node may contain significant computing resources and minimal cache
resources, making the execution node useful for tasks that require
significant computing resources. Another execution node may contain
significant cache resources and minimal computing resources, making
this execution node useful for tasks that require caching of large
amounts of data. Yet another execution node may contain cache
resources providing faster input-output operations, useful for
tasks that require fast scanning of large amounts of data. In some
embodiments, the cache resources and computing resources associated
with a particular execution node are determined when the execution
node is created, based on the expected tasks to be performed by the
execution node.
[0041] Additionally, the cache resources and computing resources
associated with a particular execution node may change over time
based on changing tasks performed by the execution node. For
example, an execution node may be assigned more processing
resources if the tasks performed by the execution node become more
processor-intensive. Similarly, an execution node may be assigned
more cache resources if the tasks performed by the execution node
require a larger cache capacity.
[0042] Although virtual warehouses 1, 2, and n are associated with
the same execution platform 110, the virtual warehouses may be
implemented using multiple computing systems at multiple geographic
locations. For example, virtual warehouse 1 can be implemented by a
computing system at a first geographic location, while virtual
warehouses 2 and n are implemented by another computing system at a
second geographic location. In some embodiments, these different
computing systems are cloud-based computing systems maintained by
one or more different entities.
[0043] Additionally, each virtual warehouse is shown in FIG. 3 as
having multiple execution nodes. The multiple execution nodes
associated with each virtual warehouse may be implemented using
multiple computing systems at multiple geographic locations. For
example, an instance of virtual warehouse 1 implements execution
nodes 302-1 and 302-2 on one computing platform at a geographic
location and implements execution node 302-n at a different
computing platform at another geographic location. Selecting
particular computing systems to implement an execution node may
depend on various factors, such as the level of resources needed
for a particular execution node (e.g., processing resource
requirements and cache requirements), the resources available at
particular computing systems, communication capabilities of
networks within a geographic location or between geographic
locations, and which computing systems are already implementing
other execution nodes in the virtual warehouse.
[0044] Execution platform 110 is also fault tolerant. For example,
if one virtual warehouse fails, that virtual warehouse is quickly
replaced with a different virtual warehouse at a different
geographic location.
[0045] A particular execution platform 110 may include any number
of virtual warehouses. Additionally, the number of virtual
warehouses in a particular execution platform is dynamic, such that
new virtual warehouses are created when additional processing
and/or caching resources are needed. Similarly, existing virtual
warehouses may be deleted when the resources associated with the
virtual warehouse are no longer necessary.
[0046] In some embodiments, the virtual warehouses may operate on
the same data in storage platform 104, but each virtual warehouse
has its own execution nodes with independent processing and caching
resources. This configuration allows requests on different virtual
warehouses to be processed independently and with no interference
between the requests. This independent processing, combined with
the ability to dynamically add and remove virtual warehouses,
supports the addition of new processing capacity for new users
without impacting the performance observed by the existing
users.
[0047] FIGS. 4A and 4B illustrates an example computing environment
400 in which an application 402 (a software application) is
connected to the database system 102, in accordance with some
embodiments of the present disclosure. As shown in FIG. 4A, the
application 402 executes on an application provider platform.
Initially, the application 402 only has access to application data
owned by the application provider (e.g., application data created
and managed by the application 402). The application data is stored
and maintained by the database system 102.
[0048] A user of the application 402 may be associated with a
customer account 404 provided by the database system 102. Customer
data 406 associated with the customer account 404 is maintained by
the database system 102. The customer account 404 within the
database system 102 is granted access to second-party application
data 408 and third-party data 410. The second-party application
data 408 can include application data corresponding to one or more
other applications. For example, the second-party application data
408 can include application data created, managed, and/or consumed
by a second application. The second-party application data 408 is
associated with one or more second-party application provider
accounts maintained by the database system 102. Each second-party
application provider account corresponds to a second-party
application provider. The third-party data 410 can include data
from one or more third-party data providers corresponding to one or
more accounts maintained by the database system 102. For example,
the third-party data 410 can include customer data associated with
a second customer account provider by the database system 102.
[0049] With reference to FIG. 4B, to enable the user of the
application 402 to provide the application 402 access to the
customer data 406 as well as the second-party application data 408
and third-party data 410, the application 402 presents a user
interface (UI) element 412 to receive security credentials
associated with the customer account 404 to authenticate the user
as an authorized user of the customer account 404. The UI element
412 can include one or more input fields along with a prompt for
the user to input security credentials associated with the customer
account 404 (e.g., a username and password). The security
credentials are provided by the application 402 to the database
system 102. The database system 102 authenticates the security
credentials, and in response to the database system 102
successfully authenticating the security credentials, the
application 402 presents UI element 414 that allows the user to
specify data to be shared with the application 402. The application
402 can display the UI element 414 in response to receiving an
indication from the database system 102 of successful
authentication or the database system 102 can cause the application
402 to display the UI element 414 (e.g., by providing instructions
to the computing device executing the application 402 that cause
the computing device to present the UI element 414) in response to
successful authentication. From the UI element 414, the user can
specify one or more databases or one or more portions of a database
to be shared with the application 402.
[0050] As an example, the user can use the UI element 414 to
establish a connection that allows the application 402 to use any
one or more of the customer data 406, the second-party application
data 408, and the third-party data 410. That is, the user can use
the UI element 414 to share data from a database that is within the
customer account 404, an account of a second-party application data
provider, or an account of a third-party data provider, or to share
data from a database that includes a combination of any one or more
of customer data, second-party application data, and third-party
data.
[0051] The user may further specify a context in which data is to
be used by the application 402. That is, the user can specify one
or more limitations on use of the data by the application 402. For
example, the user may limit access to portions of the database or
restrict access to one or more portions of the second-party
application data 408 or third-party data 410. As another example,
the user can specify read and write permissions for the application
402 associated with any one or more of the customer data 406, the
second-party application data 408, or the third-party data 410.
[0052] A request to share cloud data with the application 402 is
generated based on user input provided to the UI element 414 and
the request is submitted to the database system 102. The database
system 102 provides access to the cloud data specified in the
request to the application 402. In the example illustrated in FIG.
4B, the cloud data includes the customer data 406, the second-party
application data 408, and the third-party data 410. That is, the
database system 102 enables the application 402 to access the
customer data 406, the second-party application data 408, and the
third-party data 410 in accordance with any restrictions on use
specified in the request.
[0053] Consistent with some embodiments, prior to providing access
to the data to the application 402, the database system 102 can
perform one or more validations to validate a schema or format of
the data to ensure compatibility with the application 402. The
database system 102 may further perform one or more normalization
operations on the data prior to providing access to the application
402.
[0054] FIG. 5 illustrates an example architecture 500 to support
cloud data sharing between applications (e.g., application 402) and
the database system, in accordance with some embodiments of the
present disclosure. As shown, the architecture 500 includes an
application platform 502 that supports a multi-tenant application.
The application platform 502 utilizes data 504 that includes
application data (e.g., customer data 406) as well as data obtained
from a data marketplace 506 (e.g., second-party application data
408 and third-party data 410). Access to the data 504 can be
provisioned to customers A, B, and C of the application platform
502. As shown, customer data from a customer account within the
database system 102 is shared with and used by the application
platform 502. Second-party application data and third-party data
that the customer account is permitted to access can also be shared
with the application platform 502.
[0055] FIGS. 6 and 7 are flow diagrams illustrating operations of
the database system 102 in performing a method 600 for connecting
an application to a database system 102, in accordance with some
embodiments of the present disclosure. The method 600 may be
embodied in computer-readable instructions for execution by one or
more hardware components (e.g., one or more processors) such that
the operations of the method 600 may be performed by components of
database system 102. Accordingly, the method 600 is described
below, by way of example with reference thereto. However, it shall
be appreciated that the method 600 may be deployed on various other
hardware configurations and is not intended to be limited to
deployment within the database system 102.
[0056] Depending on the embodiment, an operation of the method 600
may be repeated in different ways or involve intervening operations
not shown. Though the operations of the method 600 may be depicted
and described in a certain order, the order in which the operations
are performed may vary among embodiments, including performing
certain operations in parallel or performing sets of operations in
separate processes. For example, although the use and generation of
the pruning index are described and illustrated together as part of
the method 600, it shall be appreciated that the use and generation
of the restricted view may be performed as separate processes,
consistent with some embodiments.
[0057] At operation 605, the database system 102 receives an
authentication request associated with a request to share customer
data with an application. The authentication request includes
security credentials (e.g., a username and password) associated
with a first account provided by the database system 102 (e.g., a
customer account). In some embodiments, the authentication request
can be received from a computing device executing the application
and based on input provided by a user via a first user interface
element presented by the application. In some embodiments, the
authentication request can be received by a computing device in
communication with the database system 102 and based on user input
provided to a UI provided by the database system 102.
[0058] At operation 610, the database system 102 authenticates the
security credentials and, based on successful authentication of the
security credentials, the database system 102 provides a UI element
to share customer data with the application, at operation 615. In
embodiments in which the authentication request is provided based
on user interaction with the application, the database system 102
may cause a computing device executing the application to display a
second UI element for the customer to share customer data with the
application.
[0059] At operation 620, the database system 102 receives a request
to share customer data in the first account with an application. In
some embodiments, the request can be received, for example, from
the computing device executing the application. The request can be
generated at the computing device executing the application based
on input received from the user associated with the first account
via the second interface element. In some embodiments, the request
is generated based on user input received via a user interface
provided by the database system 102 to a computing device without
the computing device executing the application. That is, a user can
submit a request to share data with an application from a first
computing device without interacting directly with the application
or a second computing device on which the application is
executable.
[0060] The request can specify a particular context in which the
application can use the customer data. For example, the request can
indicate one or more limits on the manner in which the customer
data is used by the application (e.g., limits on the application
read or write permissions with respect to one or more portions of
the data). As another example, the request can specify whether the
application is able to access second-party application data and/or
third-party data that is accessible by the customer account.
[0061] At operation 625, the database system 102 identifies
second-party application data that is accessible by the first
account, and at operation 625, the database system 102 identifies
third-party data that is accessible by the first account. The
second-party application data comprises application data
corresponding to a second application (e.g., data created, managed,
and/or consumed by a second application) associated with a second
account (e.g., a second-party application provider account)
maintained by the database system 102. The second account
corresponds to a second-party application provider. The third-party
data can include data from a third-party data provider
corresponding to a third account (e.g., a third-party data provider
account) maintained by the database system 102. For example, the
third-party data can correspond to customer data associated with a
second customer account provider by the database system 102. In
instances in which the request restricts access of the application
to the second-party application data or the third-party data, the
database system 102 may not perform operation 625 or 630.
[0062] At operation 635, the database system 102 enables the
application to access cloud data associated with the customer
account. The cloud data includes the customer data, the
second-party application data, and third-party data associated with
the customer account. In instances in which the request to share
the customer data includes one or more limits on use of the cloud
data, the enabling of the application to access the cloud data
further includes restricting use of the cloud data by the
application according to the one or more limits.
[0063] As shown in FIG. 7, the method 600 can further include
operations 705 and 710, in some embodiments. Consistent with these
embodiments, the operations 705 and 710 can be performed prior to
operation 635 where the database system 102 enables the application
to access the cloud data associated with the customer account.
[0064] At operation 705, the database system 102 performs one or
more validations of the cloud data to ensure it is compatible with
the application. As an example, the one or more validations can
include any one or more of validation a format of the cloud data
and validation a schema of the cloud data. At operation 710, the
database system 102 performs one or more normalizations on the
cloud data to normalize the cloud data.
[0065] FIG. 8 illustrates a diagrammatic representation of a
machine 800 in the form of a computer system within which a set of
instructions may be executed for causing the machine 800 to perform
any one or more of the methodologies discussed herein, according to
an example embodiment. Specifically, FIG. 8 shows a diagrammatic
representation of the machine 800 in the example form of a computer
system, within which instructions 816 (e.g., software, a program,
an application, an applet, an app, or other executable code) for
causing the machine 800 to perform any one or more of the
methodologies discussed herein may be executed. For example, the
instructions 816 may cause the machine 800 to execute any one or
more operations of the method 600. As another example, the
instructions 816 may cause the machine 800 to implement portions of
the functionality illustrated in any one or more of FIGS. 4A, 4B,
and 5. In this way, the instructions 816 transform a general,
non-programmed machine into a particular machine 800 (e.g., the
compute service manager 108, the execution platform 110, and the
computing device 112) that is specially configured to carry out any
one of the described and illustrated functions in the manner
described herein.
[0066] In alternative embodiments, the machine 800 operates as a
standalone device or may be coupled (e.g., networked) to other
machines. In a networked deployment, the machine 800 may operate in
the capacity of a server machine or a client machine in a
server-client network environment, or as a peer machine in a
peer-to-peer (or distributed) network environment. The machine 800
may comprise, but not be limited to, a server computer, a client
computer, a personal computer (PC), a tablet computer, a laptop
computer, a netbook, a smart phone, a mobile device, a network
router, a network switch, a network bridge, or any machine capable
of executing the instructions 816, sequentially or otherwise, that
specify actions to be taken by the machine 800. Further, while only
a single machine 800 is illustrated, the term "machine" shall also
be taken to include a collection of machines 800 that individually
or jointly execute the instructions 816 to perform any one or more
of the methodologies discussed herein.
[0067] The machine 800 includes processors 810, memory 830, and
input/output (I/O) components 850 configured to communicate with
each other such as via a bus 802. In an example embodiment, the
processors 810 (e.g., a central processing unit (CPU), a reduced
instruction set computing (RISC) processor, a complex instruction
set computing (CISC) processor, a graphics processing unit (GPU), a
digital signal processor (DSP), an application-specific integrated
circuit (ASIC), a radio-frequency integrated circuit (RFIC),
another processor, or any suitable combination thereof) may
include, for example, a processor 812 and a processor 814 that may
execute the instructions 816. The term "processor" is intended to
include multi-core processors 810 that may comprise two or more
independent processors (sometimes referred to as "cores") that may
execute instructions 816 contemporaneously. Although FIG. 8 shows
multiple processors 810, the machine 800 may include a single
processor with a single core, a single processor with multiple
cores (e.g., a multi-core processor), multiple processors with a
single core, multiple processors with multiple cores, or any
combination thereof.
[0068] The memory 830 may include a main memory 832, a static
memory 834, and a storage unit 836, all accessible to the
processors 810 such as via the bus 802. The main memory 832, the
static memory 834, and the storage unit 836 store the instructions
816 embodying any one or more of the methodologies or functions
described herein. The instructions 816 may also reside, completely
or partially, within the main memory 832, within the static memory
834, within the storage unit 836, within at least one of the
processors 810 (e.g., within the processor's cache memory), or any
suitable combination thereof, during execution thereof by the
machine 800.
[0069] The I/O components 850 include components to receive input,
provide output, produce output, transmit information, exchange
information, capture measurements, and so on. The specific I/O
components 850 that are included in a particular machine 800 will
depend on the type of machine. For example, portable machines such
as mobile phones will likely include a touch input device or other
such input mechanisms, while a headless server machine will likely
not include such a touch input device. It will be appreciated that
the I/O components 850 may include many other components that are
not shown in FIG. 8. The I/O components 850 are grouped according
to functionality merely for simplifying the following discussion
and the grouping is in no way limiting. In various example
embodiments, the I/O components 850 may include output components
852 and input components 854. The output components 852 may include
visual components (e.g., a display such as a plasma display panel
(PDP), a light emitting diode (LED) display, a liquid crystal
display (LCD), a projector, or a cathode ray tube (CRT)), acoustic
components (e.g., speakers), other signal generators, and so forth.
The input components 854 may include alphanumeric input components
(e.g., a keyboard, a touch screen configured to receive
alphanumeric input, a photo-optical keyboard, or other alphanumeric
input components), point-based input components (e.g., a mouse, a
touchpad, a trackball, a joystick, a motion sensor, or another
pointing instrument), tactile input components (e.g., a physical
button, a touch screen that provides location and/or force of
touches or touch gestures, or other tactile input components),
audio input components (e.g., a microphone), and the like.
[0070] Communication may be implemented using a wide variety of
technologies. The I/O components 850 may include communication
components 864 operable to couple the machine 800 to a network 870
or devices 880 via a coupling 872 and a coupling 882, respectively.
For example, the communication components 864 may include a network
interface component or another suitable device to interface with
the network 870. In further examples, the communication components
864 may include wired communication components, wireless
communication components, cellular communication components, and
other communication components to provide communication via other
modalities. The devices 880 may be another machine or any of a wide
variety of peripheral devices (e.g., a peripheral device coupled
via a universal serial bus (USB)). For example, as noted above, the
machine 800 may correspond to any one of the compute service
manager 108, the execution platform 110, and the devices 880 may
include the data storage device 206 or any other computing device
described herein as being in communication with the database system
102 or the storage platform 104.
Executable Instructions and Machine Storage Medium
[0071] The various memories (e.g., 830, 832, 834, and/or memory of
the processor(s) 810 and/or the storage unit 836) may store one or
more sets of instructions 816 and data structures (e.g., software)
embodying or utilized by any one or more of the methodologies or
functions described herein. These instructions 816, when executed
by the processor(s) 810, cause various operations to implement the
disclosed embodiments.
[0072] As used herein, the terms "machine-storage medium,"
"device-storage medium," and "computer-storage medium" mean the
same thing and may be used interchangeably in this disclosure. The
terms refer to a single or multiple storage devices and/or media
(e.g., a centralized or distributed database, and/or associated
caches and servers) that store executable instructions and/or data.
The terms shall accordingly be taken to include, but not be limited
to, solid-state memories, and optical and magnetic media, including
memory internal or external to processors. Specific examples of
machine-storage media, computer-storage media, and/or
device-storage media include non-volatile memory, including by way
of example semiconductor memory devices, e.g., erasable
programmable read-only memory (EPROM), electrically erasable
programmable read-only memory (EEPROM), field-programmable gate
arrays (FPGAs), and flash memory devices; magnetic disks such as
internal hard disks and removable disks; magneto-optical disks; and
CD-ROM and DVD-ROM disks. The terms "machine-storage media,"
"computer-storage media," and "device-storage media" specifically
exclude carrier waves, modulated data signals, and other such
media, at least some of which are covered under the term "signal
medium" discussed below.
Transmission Medium
[0073] In various example embodiments, one or more portions of the
network 870 may be an ad hoc network, an intranet, an extranet, a
virtual private network (VPN), a local-area network (LAN), a
wireless LAN (WLAN), a wide-area network (WAN), a wireless WAN
(WWAN), a metropolitan-area network (MAN), the Internet, a portion
of the Internet, a portion of the public switched telephone network
(PSTN), a plain old telephone service (POTS) network, a cellular
telephone network, a wireless network, a Wi-Fi.RTM. network,
another type of network, or a combination of two or more such
networks. For example, the network 870 or a portion of the network
870 may include a wireless or cellular network, and the coupling
872 may be a Code Division Multiple Access (CDMA) connection, a
Global System for Mobile communications (GSM) connection, or
another type of cellular or wireless coupling. In this example, the
coupling 872 may implement any of a variety of types of data
transfer technology, such as Single Carrier Radio Transmission
Technology (1.times.RTT), Evolution-Data Optimized (EVDO)
technology, General Packet Radio Service (GPRS) technology,
Enhanced Data rates for GSM Evolution (EDGE) technology, third
Generation Partnership Project (3GPP) including 3G, fourth
generation wireless (4G) networks, Universal Mobile
Telecommunications System (UMTS), High-Speed Packet Access (HSPA),
Worldwide Interoperability for Microwave Access (WiMAX), Long Term
Evolution (LTE) standard, others defined by various
standard-setting organizations, other long-range protocols, or
other data transfer technology.
[0074] The instructions 816 may be transmitted or received over the
network 870 using a transmission medium via a network interface
device (e.g., a network interface component included in the
communication components 864) and utilizing any one of a number of
well-known transfer protocols (e.g., hypertext transfer protocol
(HTTP)). Similarly, the instructions 816 may be transmitted or
received using a transmission medium via the coupling 882 (e.g., a
peer-to-peer coupling) to the devices 880. The terms "transmission
medium" and "signal medium" mean the same thing and may be used
interchangeably in this disclosure. The terms "transmission medium"
and "signal medium" shall be taken to include any intangible medium
that is capable of storing, encoding, or carrying the instructions
816 for execution by the machine 800, and include digital or analog
communications signals or other intangible media to facilitate
communication of such software. Hence, the terms "transmission
medium" and "signal medium" shall be taken to include any form of
modulated data signal, carrier wave, and so forth. The term
"modulated data signal" means a signal that has one or more of its
characteristics set or changed in such a manner as to encode
information in the signal.
Computer-Readable Medium
[0075] The terms "machine-readable medium," "computer-readable
medium," and "device-readable medium" mean the same thing and may
be used interchangeably in this disclosure. The terms are defined
to include both machine-storage media and transmission media. Thus,
the terms include both storage devices/media and carrier
waves/modulated data signals.
[0076] The various operations of example methods described herein
may be performed, at least partially, by one or more processors
that are temporarily configured (e.g., by software) or permanently
configured to perform the relevant operations. Similarly, the
methods described herein may be at least partially
processor-implemented. For example, at least some of the operations
of the method 600 may be performed by one or more processors. The
performance of certain of the operations may be distributed among
the one or more processors, not only residing within a single
machine, but also deployed across a number of machines. In some
example embodiments, the processor or processors may be located in
a single location (e.g., within a home environment, an office
environment, or a server farm), while in other embodiments the
processors may be distributed across a number of locations.
[0077] Although the embodiments of the present disclosure have been
described with reference to specific example embodiments, it will
be evident that various modifications and changes may be made to
these embodiments without departing from the broader scope of the
inventive subject matter. Accordingly, the specification and
drawings are to be regarded in an illustrative rather than a
restrictive sense. The accompanying drawings that form a part
hereof show, by way of illustration, and not of limitation,
specific embodiments in which the subject matter may be practiced.
The embodiments illustrated are described in sufficient detail to
enable those skilled in the art to practice the teachings disclosed
herein. Other embodiments may be used and derived therefrom, such
that structural and logical substitutions and changes may be made
without departing from the scope of this disclosure. This Detailed
Description, therefore, is not to be taken in a limiting sense, and
the scope of various embodiments is defined only by the appended
claims, along with the full range of equivalents to which such
claims are entitled.
[0078] Such embodiments of the inventive subject matter may be
referred to herein, individually and/or collectively, by the term
"invention" merely for convenience and without intending to
voluntarily limit the scope of this application to any single
invention or inventive concept if more than one is in fact
disclosed. Thus, although specific embodiments have been
illustrated and described herein, it should be appreciated that any
arrangement calculated to achieve the same purpose may be
substituted for the specific embodiments shown. This disclosure is
intended to cover any and all adaptations or variations of various
embodiments. Combinations of the above embodiments, and other
embodiments not specifically described herein, will be apparent, to
those of skill in the art, upon reviewing the above
description.
[0079] In this document, the terms "a" or "an" are used, as is
common in patent documents, to include one or more than one,
independent of any other instances or usages of "at least one" or
"one or more." In this document, the term "or" is used to refer to
a nonexclusive or, such that "A or B" includes "A but not B," "B
but not A," and "A and B," unless otherwise indicated. In the
appended claims, the terms "including" and "in which" are used as
the plain-English equivalents of the respective terms "comprising"
and "wherein." Also, in the following claims, the terms "including"
and "comprising" are open-ended; that is, a system, device,
article, or process that includes elements in addition to those
listed after such a term in a claim is still deemed to fall within
the scope of that claim.
* * * * *