Truncating data associated with objects in a multi-tenant database

• US 9,558,218 B2
• Filed: 05/18/2015
• Issued: 01/31/2017
• Est. Priority Date: 07/01/2011
• Status: Active Grant

• Current Assignee: Salesforce.com, Inc.
• Original Assignee: Salesforce.com, Inc.
• Inventors: Dutta, Arup, Wong, Simon, Soble, Dan, Black, Nathanael, Macklem, Walter
• Primary Examiner(s): Lee, Wilson
• Application Number:
  US14/714,968
• Publication Number:
  US 20150254286A1
• Time in Patent Office: 624 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06F 16/162 Delete operations erasing in storage systems G06F3/0652
• CPC Class Codes: G06F 16/176 Support for shared access to files; File sharing support
• CPC Class Codes: G06F 16/215 Improving data quality; Data cleansing, e.g. de-duplication, removing invalid entries or correcting typographical errors
• CPC Class Codes: G06F 16/907 Retrieval characterised by using metadata, e.g. metadata not derived from the content or metadata generated manually

Abstract

An exemplary embodiment of a multi-tenant database system is provided. The system includes a multi-tenant database, an entity definition table, and a data processing engine. The database has database objects for multiple tenants, including an existing object for a designated tenant. Each entry in the existing object has a respective entity identifier. The definition table has metadata entries for the database objects, including a metadata entry for the existing object. This metadata entry has a tenant identifier for the designated tenant, an entity name for the existing object, and an old key prefix for the existing object. Each entity identifier of the existing object begins with the old key prefix. The engine performs a data truncation operation on the existing object by updating the metadata entry to replace the old key prefix with a new key prefix. This results in an updated object that is identified by the new key prefix and the tenant identifier.

Claims

1. A computer-implemented method of truncating data from a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier, the method comprising:

maintaining an entity definition table having a plurality of metadata entries corresponding to the database objects, including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object;

obtaining an instruction to remove all data from the existing database object; and

in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

each entry in the existing database object is uniquely associated with a respective entity identifier that begins with the old key prefix; and

each entry in the updated database object is uniquely associated with a respective entity identifier that begins with the new key prefix.

2. The computer-implemented method of claim 1, wherein updating the metadata entry disassociates previously stored data from the old key prefix.

3. The computer-implemented method of claim 1, further comprising initiating display of a graphical representation of an empty object that corresponds to the updated database object.

4. The computer-implemented method of claim 1, further comprising creating a soft deleted database object that is identified by the old key prefix and the tenant identifier.

5. The computer-implemented method of claim 1, wherein each entry in the multi-tenant database is identified by a unique entity identifier.

6. The computer-implemented method of claim 1, wherein:

the metadata entry includes the old key prefix in a key prefix field; and

updating the metadata entry is performed to include the new key prefix in the key prefix field, to obtain an updated metadata entry that corresponds to the updated database object.

7. A multi-tenant database system comprising:

a data storage system implementing a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier;

an entity definition table having a plurality of metadata entries corresponding to the database objects, and including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object; and

processing hardware comprising a processor configured to perform a data truncation operation on the existing database object by obtaining an instruction to remove all data from the existing database object, and, in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

each entry in the existing database object is uniquely associated with a respective entity identifier that begins with the old key prefix; and

each entry in the updated database object is uniquely associated with a respective entity identifier that begins with the new key prefix.

8. The multi-tenant database system of claim 7, wherein the processor is configured to create a soft deleted database object that is identified by the old key prefix and the tenant identifier.

9. The multi-tenant database system of claim 8, wherein the processor is configured to delete the soft deleted database object after a designated time period ends.

10. The multi-tenant database system of claim 7, wherein updating the metadata entry disassociates previously stored data from the old key prefix.

11. The multi-tenant database system of claim 7, wherein each entry in the multi-tenant database is identified by a unique entity identifier.

12. The multi-tenant database system of claim 7, wherein:

the metadata entry includes the old key prefix in a key prefix field; and

updating the metadata entry is performed to include the new key prefix in the key prefix field, to obtain an updated metadata entry that corresponds to the updated database object.

13. A computer-implemented method of truncating data from a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier, the method comprising:

maintaining an entity definition table having a plurality of metadata entries corresponding to the database objects, including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object;

obtaining an instruction to remove all data from the existing database object; and

in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

the existing database object includes a first entry that is linked to a foreign key maintained in a second entry of a target database object, the foreign key stored in a field identified by a first column number; and

updating the metadata entry comprises altering metadata for the second entry of the target database object by replacing the first column number with a new and previously unused column number.

14. A computer-implemented method of truncating data from a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier, the method comprising:

maintaining an entity definition table having a plurality of metadata entries corresponding to the database objects, including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object;

obtaining an instruction to remove all data from the existing database object; and

in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

the existing database object includes a first entry that is linked to a foreign key maintained in a second entry of a target database object; and

the method further comprises removing the second entry of the target database object in response to replacing the old key prefix with the new key prefix.

15. A computer-implemented method of truncating data from a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier, the method comprising:

maintaining an entity definition table having a plurality of metadata entries corresponding to the database objects, including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object;

obtaining an instruction to remove all data from the existing database object; and

in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

the existing database object includes a first entry that is linked to a summary field value maintained in a second entry of a target database object; and

the method further comprises updating the summary field value in response to replacing the old key prefix with the new key prefix.

16. A multi-tenant database system comprising:

a data storage system implementing a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier;

an entity definition table having a plurality of metadata entries corresponding to the database objects, and including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object; and

processing hardware comprising a processor configured to perform a data truncation operation on the existing database object by obtaining an instruction to remove all data from the existing database object, and, in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

the existing database object includes a first entry that is linked to a foreign key maintained in a second entry of a target database object, the foreign key stored in a field identified by a first column number; and

updating the metadata entry comprises altering metadata for the second entry of the target database object by replacing the first column number with a new and previously unused column number.

17. A multi-tenant database system comprising:

a data storage system implementing a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier;

an entity definition table having a plurality of metadata entries corresponding to the database objects, and including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object; and

processing hardware comprising a processor configured to perform a data truncation operation on the existing database object by obtaining an instruction to remove all data from the existing database object, and, in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

the existing database object includes a first entry that is linked to a foreign key maintained in a second entry of a target database object; and

the method further comprises removing the second entry of the target database object in response to replacing the old key prefix with the new key prefix.

18. A multi-tenant database system comprising:

a data storage system implementing a multi-tenant database that maintains database objects for a plurality of different tenants, each database object in the multi-tenant database being identified by a unique combination of a key prefix and a tenant identifier;

an entity definition table having a plurality of metadata entries corresponding to the database objects, and including a metadata entry for an existing database object, the metadata entry comprising a tenant identifier for a particular tenant associated with the existing database object, an entity name for the existing database object, and an old key prefix for the existing database object; and

processing hardware comprising a processor configured to perform a data truncation operation on the existing database object by obtaining an instruction to remove all data from the existing database object, and, in response to obtaining the instruction, updating the metadata entry to replace the old key prefix with a new key prefix that is not currently associated with any other database object for the particular tenant, wherein updating the metadata entry results in an updated database object that is identified by the new key prefix and the tenant identifier, wherein;

the existing database object includes a first entry that is linked to a summary field value maintained in a second entry of a target database object; and

the method further comprises updating the summary field value in response to replacing the old key prefix with the new key prefix.