Techniques for performing view indication management

• US 8,914,404 B1
• Filed: 03/29/2011
• Issued: 12/16/2014
• Est. Priority Date: 03/29/2011
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Kim, Ken, Wang, Yong, Bailey, Lorenzo, Djunaedi, Muhamad, Tang, Xuan, Vipul, Utkarsh
• Primary Examiner(s): LE, UYEN T
• Application Number:
  US13/065,738
• Time in Patent Office: 1,358 Days
• Field of Search: None
• US Class Current: 707/769
• CPC Class Codes: G06F 16/2358 Change logging, detection, and notification replication G06F16/27

Abstract

Described are techniques for providing notifications. A client registers a subscription request for a view to provide a notification to the client responsive to a data change affecting the view. The view is generated using one or more commands operating on data included in a database. A first operation is performed to the database. It is determined whether the first operation causes a data change affecting the view. Responsive to determining the first operation causes a data change affecting the view, a notification is sent to the client. The view is updated in response to receiving the notification.

Claims

1. A method for providing notifications comprising:

registering, by a client, a subscription request for a view to provide a notification to the client responsive to a data change affecting the view, wherein the view is generated using one or more commands operating on data included in a database;

performing a first operation to the database;

determining whether the first operation causes a data change affecting the view;

responsive to determining the first operation causes a data change affecting the view, sending a notification from an indication manager to the client thereby pushing the notification to the client regarding the data change without having the client poll for any data changes affecting the view; and

updating the view in response to receiving the notification, wherein the view is accessible as a virtual table computed using one or more database tables of the database, wherein each of the one or more database tables corresponds to a class of object instances, each row of said each database table includes data for one of said object instances, and said each row includes property or attribute values for said one object instance, wherein each object instance identified by a corresponding row in one of the one or more database tables represents any of a physical entity and a logical entity in a data storage system, wherein at least one object represented by a corresponding row in one of the one or more database tables represents a first logical entity that is any of a RAID group, a logical device, and a storage group of one or more logical devices.

2. The method of claim 1, wherein the view is updated using information returned in the notification.

3. The method of claim 1, wherein the one or more commands are database query commands which extract data from the one or more database tables.

4. The method of claim 3, wherein the first operation is a command to perform any of an update operation to update an existing row of a first of the one of the database tables, a new operation to add a new row to the first database table and a delete operation to delete an existing row of the first database table.

5. The method of claim 4, wherein the subscription request includes criteria to register to receive a notification in response to an occurrence of any of a deletion of an existing row from the virtual table representing the view, an update of one or more data items included in an existing row from the virtual table representing the view, and a new operation causing an addition of a new row to the virtual table representing the view.

6. The method of claim 5, wherein the criteria indicates to register to receive a notification in response to any of an occurrence of a deletion of a row from the virtual table of the view and a new operation to add a new row of data to the virtual table of the view, and the method further comprising:

determining that the first database table includes data upon which said view is dependent;

setting one or more database triggers for the first database table, said one or more database triggers providing for notification to a first software component upon an occurrence of any of a new operation to insert a new row in the first database table, a delete operation to delete an existing row from the database table, and an update operation to update a column of the first database table, wherein a primary key of the virtual table of the view is dependent upon the column; and

caching a first set of one or more values for the primary key, said first set of one or more values corresponding to current values of the primary key included in the virtual table of the view.

7. The method of claim 6, wherein the criteria indicates to register to receive a notification in response to an occurrence of a new operation to add a new row of data to the virtual table, and the method further comprising:

receiving a database trigger notification that a new row having a first row identifier has been added to the first database table;

determining that the view has a data dependency on data of the new row;

performing a query based on at least a first of said one or more database query commands with additional query criteria to retrieve data of the first database table matching said first row identifier, said query returning first results;

determining whether the first results includes a first value that does not match one of the values of the first set previously cached; and

if the first results includes the first value that does not match one of the values of the first set, sending a new notification to the client and updating a cache to include the first value.

8. The method of claim 6, wherein the criteria indicates to register to receive a notification in response to an occurrence of a delete operation to delete an existing row of data from the virtual table, and the method further comprising:

receiving a database trigger notification that a first row having a first row identifier has been deleted from the first database table;

determining that the view has a data dependency on data of the first row that has been deleted;

performing a query based on at least a first of said one or more database query commands to return first results including a list of one or more current values of the primary key of the virtual table of the view;

comparing the list to the first set previously cached; and

for each value included in the first set which does not have a match in the list, sending a deletion notification to the client and updating a cache to remove said each value.

9. The method of claim 5, wherein the criteria indicates to register to receive a notification in response to an occurrence of an update or change operation to update any existing data included in a first column of the virtual table of the view, wherein the first column corresponds to an object property of interest, and the method further comprising:

determining that the first database table includes data upon which said view is dependent;

determining a second column of the first database table, wherein the first column of the virtual table of the view corresponds to or otherwise depends upon the second column;

setting one or more database triggers for the first database table, said one or more database triggers providing for notification to a first software component upon an occurrence of any of an insert operation to insert a new row in the first database table, a delete operation to delete an existing row from the database table, an update operation to update the second column of the first database table, and an update operation to update a column of the first database table, wherein a primary key of the virtual table of the view depends on the column;

caching a first set of one or more values for the primary key of the virtual table of the view, said first set of one or more values corresponding to current values of the primary key included in the virtual table of the view; and

caching a second set of one or more values of the first column of the virtual table, said second set of one or more values corresponding to current values included in the first column of the virtual table, each value in said second set having a corresponding value in said first set.

10. The method of claim 9, further comprising:

receiving a database trigger notification that a first database operation has been performed to update existing data of a first row having a first row identifier from the first database table;

determining that the view has a data dependency on data of the first row;

performing a query based on at least a first of said one or more database query commands with additional query criteria to retrieve data of the first database table matching said first row identifier, said query returning first results corresponding to a second row of the virtual table dependent on the first database operation performed, said first results including a first primary key value for the primary key of the virtual table and a first property value of the object property of interest;

comparing the first results to the first set and the second set to determine if there has been a change to any one or more values of the object property of interest; and

for each value included in the second set that is associated with a corresponding value in the first set and that is identified as having changed by said comparing, sending a change notification to the client and updating a cache to include an updated data value for said each value.

11. The method of claim 3, wherein the one or more commands include at least one command which aggregates first data from the one or more database tables and includes in the view one or more data items in accordance with the aggregated first data.

12. The method of claim 11, wherein the first data includes a mathematical calculation using a plurality of data items from the one or more database tables.

13. The method of claim 11, wherein the one or more commands include at least one command which joins data from multiple database tables to form a row of the virtual table of the view.

14. A non-transitory computer readable medium comprising code stored thereon for providing notifications, the non-transitory computer readable medium comprising code for:

registering, by a client, a subscription request for a view to provide a notification to the client responsive to a data change affecting the view, wherein the view is generated using one or more commands operating on data included in a database;

performing a first operation to the database;

determining whether the first operation causes a data change affecting the view;

responsive to determining the first operation causes a data change affecting the view, sending a notification from an indication manager to the client thereby pushing the notification to the client regarding the data change without having the client poll for any data changes affecting the view; and

updating the view in response to receiving the notification wherein the view is accessible as a virtual table computed using one or more database tables of the database, wherein each of the one or more database tables corresponds to a class of object instances, each row of said each database table includes data for one of said object instances, and said each row includes property or attribute values for said one object instance, wherein each object instance identified by a corresponding row in one of the one or more database tables represents any of a physical entity and a logical entity in a data storage system, wherein at least one object represented by a corresponding row in one of the one or more database tables represents a first logical entity that is any of a RAID group, a logical device, and a storage group of one or more logical devices.

15. The non-transitory computer readable medium of claim 14, wherein the one or more commands are database query commands which extract data from the one or more database tables.

16. The non-transitory computer readable medium of claim 15, wherein the first operation is a command to perform any of an update operation to update an existing row of a first of the one of the database tables, a new operation to add a new row to the first database table and a delete operation to delete an existing row of the first database table.