Selectively upgrading clients in a multi-tenant computing system

• US 8,380,667 B2
• Filed: 08/11/2010
• Issued: 02/19/2013
• Est. Priority Date: 08/11/2010
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Driesen, Volker
• Primary Examiner(s): Yen, Syling
• Application Number:
  US12/854,766
• Publication Number:
  US 20120041988A1
• Time in Patent Office: 923 Days
• Field of Search: 707/610, 707/611, 707/613, 707/617, 707/618, 707/620, 707/624, 707/626, 707/634, 707/635, 707/636, 707/637, 707/639, 707/640, 707/661, 707/674, 707/999.204
• US Class Current: 707/624
• CPC Class Codes: G06F 16/213 with details for schema evolution support

Abstract

An application server in a multi-tenant computing system is enabled access to a first set of tables and views in a database according to a first schema. The views in the first schema correspond to a table in a second schema. Thereafter, the table in the second schema is modified to add a column. Views of the modified table as defined by the second schema are generated in a third schema so that the third schema defines a second set of tables and views in the database. Subsequently, access by the application server to the second set of tables and views in the database is enabled and access by the application server to the first set of tables and views in the database is prevented. Related apparatus, systems, techniques and articles are also described.

Claims

1. A computer-implemented method comprising:

enabling, in a multi-tenant computing system, an application server to access a first set of tables and views in a database according to a first schema, each table being associated with one or more corresponding tenants of the multi-tenant computing system, the views in the first schema corresponding to a table in a second schema, the table in the second schema being associated with at least one tenant;

modifying the table in the second schema to add a column, the modifying being performed separately for different tenants such that a software upgrade associated with each tenant occurs during a corresponding separate time period;

generating views of the modified table as defined by the second schema in a third schema so that the third schema defines a second set of tables and views in the database; and

enabling the application server to access the second set of tables and views in the database and preventing access by the application server to the first set of tables and views in the database;

wherein;

the multi-tenant computing system forms part of a multi-tenant environment using a single software delivery architecture,

the separate software upgrade for each tenant allows the software upgrade of a first tenant to occur during a downtime for the first tenant and an uptime for a second tenant,

the multi-tenant computing system comprises;

at least one data repository containing;

core software platform content relating to the operation of the multi-tenant computing system which is not modifiable by the multiple tenants;

system content including data objects created in runtime by the multi-tenant computing system that are modifiable with data provided by a corresponding tenant, and

tenant content including data objects or extensions to data objects that are customized for a corresponding tenant, wherein data objects or extensions to data objects of a particular tenant are not available to other tenants.

2. A method as in claim 1, wherein the tables according to the first and third schemas are repository tables.

3. A method as in claim 2, wherein the table according to the second schema is an application table.

4. A method as in claim 1, wherein the views in the first set of tables and views are deleted after access by the application server to the second set of tables and views is enabled.

5. A method as in claim 1, wherein the generated views are provided with data characterizing a structure of the modified table.

6. A method as in claim 1, wherein the generated views are provided with access permissions such that the third schema is granted access to the contents of tables in the first schema.

7. A method comprising:

enabling, in a multi-tenant computing system, a first application server to access a first set of tables and views in a database according to a first schema, the views in the first schema corresponding to a table in a second schema;

modifying a structure of the table in the second schema, the modifying being performed separately for different tenants of the multi-tenant computing system such that the separate modifying allows an upgrade of a first tenant to occur during a downtime for the first tenant and during an uptime for a second tenant;

generating views of the modified table as defined by the second schema in a third schema so that the third schema defines a second set of tables and views in the database; and

enabling a second application server to access the second set of tables and views in the database and preventing access by the first application server to the first set of tables and views in the database;

wherein;

the multi-tenant computing system forms part of a multi-tenant environment using a single software delivery architecture,

the separate software upgrade for each tenant allows the software upgrade of a first tenant to occur during a downtime for the first tenant and an uptime for a second tenant,

the multi-tenant computing system comprises;

at least one data repository containing;

core software platform content relating to the operation of the multi-tenant computing system which is not modifiable by the multiple tenants;

system content including data objects created in runtime by the multi-tenant computing system that are modifiable with data provided by a corresponding tenant, and

tenant content including data objects or extensions to data objects that are customized for a corresponding tenant, wherein data objects or extensions to data objects of a particular tenant are not available to other tenants.

8. A method as in claim 7, wherein the tables according to the first and third schemas are repository tables.

9. A method as in claim 8, wherein the table according to the second schema is an application table.

10. A method as in claim 7, wherein the views in the first set of tables and views are deleted after access by the second application server to the second set of tables and views is enabled.

11. A method as in claim 7, wherein the generated views are provided with data characterizing a structure of the modified table.

12. A method as in claim 7, wherein the generated views are provided with access permissions such that the third schema is granted access to the contents of tables in the first schema.

13. A method for implementation in a database, the database comprising a first schema and a second schema having application tables, the first schema having first repository tables and first application views of the application tables, a first application server connecting to the database using the first schema, the method comprising:

generating a third repository schema having second repository tables;

modifying a structure of the application tables in the second schema, the modifying being performed on a tenant-by-tenant basis such that a software upgrade associated with two or more tenants occurs during a separate time period, the separate software upgrade for each tenant comprising the software upgrade of a first tenant occurring during a downtime for the first tenant and an uptime for a second tenant;

generating second application views in the third schema to reflect the modified structure of the application tables in the second schema;

connecting a second application server to the database using the third schema;

disabling access to the database by the first application server; and

enabling access to the database by the second application server,

wherein;

the multi-tenant computing system forms part of a multi-tenant environment using a single software delivery architecture,

the separate software upgrade for each tenant allows the software upgrade of a first tenant to occur during a downtime for the first tenant and an uptime for a second tenant,

the multi-tenant computing system comprises;

at least one data repository containing;

core software platform content relating to the operation of the multi-tenant computing system which is not modifiable by the multiple tenants;

system content including data objects created in runtime by the multi-tenant computing system that are modifiable with data provided by a corresponding tenant, and

tenant content including data objects or extensions to data objects that are customized for a corresponding tenant, wherein data objects or extensions to data objects of a particular tenant are not available to other tenants.

14. A method as in claim 13, further comprising:

deleting the first repository tables and the first application view.

15. A method as in claim 13, further comprising:

deleting a kernel associated with the first application server.