Online updates to schema information in multi-tenant database system

1. A method, comprising:

storing, by a multi-tenant database system, a standard schema for a database object, wherein the standard schema is shared by multiple tenants;

storing, by the multi-tenant database system, a tenant-specific schema for the database object, wherein the tenant-specific schema includes one or more tenant-specific custom elements for the database object; and

checking, by the multi-tenant database system, tenant-specific custom elements for a predetermined pattern to enforce a naming scheme;

automatically adding, by the multi-tenant database system, the predetermined pattern in response to the check determining that a tenant-specific custom element does not include the predetermined pattern, wherein the predetermined pattern is not included in object elements of the standard schema;

detecting, by the multi-tenant database system, an update of the standard schema; and

in response to the detecting, the multi-tenant database system automatically propagating the update to the tenant-specific schema, while the database remains available to accept tenant queries of a tenant corresponding to the tenant-specific schema, without taking the database offline for the update.

2. The method of claim 1 , wherein the multi-tenant database system stores data for a tenant according to both the standard schema and the tenant-specific schema for the database object in a non-relational underlying storage format.

3. The method of claim 2 , further comprising:

processing change records from a change stream for the non-relational underlying storage format, wherein the detecting the update of the standard schema and the automatic propagation are based on a change record for the update in the change stream.

4. The method of claim 1 , wherein the standard schema is stored using a top-level scope and the tenant-specific schema is stored in a tenant namespace scope.

5. The method of claim 4 , further comprising:

creating, by the multi-tenant database system, the tenant namespace scope and the top-level scope;

configuring, by the multi-tenant database system, multitenancy settings for the top-level scope based on one or more commands received via a provisioning application programming interface (API);

updating, by the multi-tenant database system, the tenant-specific schema based on one or more commands received via a metadata API; and

updating, by the multi-tenant database system, a database object that conforms with the tenant-specific schema based on one or more commands received via a data API.

6. The method of claim 1 , further comprising maintaining state information for the standard schema that supports at least the following states:

a creating state;

an active state;

an updating state; and

one or more states in which at least a portion of the standard schema is being propagated to multiple tenants.

7. The method of claim 6 , further comprising maintaining state information for the tenant-specific schema that supports at least the following states:

a creating state;

an active state; and

an updating state.

8. The method of claim 1 , wherein the storing the tenant-specific schema includes storing, for different tenants, multiple different tenant-specific schemas associated with the standard schema.

9. The method of claim 1 , further comprising:

in response to creation of a tenant-defined database object, automatically storing a tenant-specific schema for the tenant-defined database object.

10. A non-transitory computer-readable medium having computer instructions stored thereon that, when executed by a multi-tenant database system, cause operations comprising:

storing a standard schema for a database object, wherein the standard schema is shared by multiple tenants;

storing a tenant-specific schema for the database object, wherein the tenant-specific schema includes one or more tenant-specific custom elements for the database object; and

checking tenant-specific custom elements for a predetermined pattern to enforce a naming scheme;

automatically adding the predetermined pattern in response to the check determining that a tenant-specific custom element does not include a predetermined pattern, wherein the predetermined pattern is not included in object elements of the standard schema;

detecting an update of the standard schema; and

in response to the detecting, automatically propagating the update to the tenant-specific schema, while the database remains available to accept tenant queries of a tenant corresponding to the tenant-specific schema, without taking the database offline for the update.

11. The non-transitory computer-readable medium of claim 10 , wherein the operations further comprise:

storing data for a tenant according to both the standard schema and the tenant-specific schema for the database object in a non-relational underlying storage format.

12. The non-transitory computer-readable medium of claim 10 , wherein the operations further comprise:

asynchronously processing change records from a change stream, wherein the detecting the update of the standard schema and automatic propagation is based on a change record for the update in the change stream.

13. The non-transitory computer-readable medium of claim 10 , wherein the standard schema is stored using a top-level scope and the tenant-specific schema is stored in a tenant namespace scope, the operations further comprising:

creating the tenant namespace scope and the top-level scope;

configuring multitenancy settings for the top-level scope based on one or more commands received via a provisioning application programming interface (API);

updating the tenant-specific schema based on one or more commands received via a metadata API; and

updating a database object that conforms with the tenant-specific schema based on one or more commands received via a data API.

14. The non-transitory computer-readable medium of claim 10 , wherein the operations further comprise:

maintaining state information for the standard schema that supports at least the following states:

a creating state;

an active state;

an updating state; and

one or more states in which at least a portion of the standard schema is being propagated to multiple tenants; and

maintaining state information for the tenant-specific schema that supports at least the following states:

a creating state;

an active state; and

an updating state.

15. The non-transitory computer-readable medium of claim 10 , wherein the storing the tenant-specific schema includes storing, for different tenants, multiple different tenant-specific schemas associated with the standard schema.

16. The non-transitory computer-readable medium of claim 10 , wherein the operations further comprise:

in response to creation of a tenant-defined database object, automatically storing a tenant-specific schema for the tenant-defined database object.

17. A system comprising:

one or more processors; and

one or more storage elements having computer instructions stored thereon that are capable of being executed by the one or more processors to:

store a standard schema for a database object, wherein the standard schema is shared by multiple tenants;

store a tenant-specific schema for the database object, wherein the tenant-specific schema includes one or more tenant-specific custom elements for the database object;

check tenant-specific custom elements for a predetermined pattern to enforce a naming scheme;

automatically add the predetermined pattern in response to the check determining that a tenant-specific custom element does not include a predetermined pattern, wherein the predetermined pattern is not included in object elements of the standard schema;

detect an update of the standard schema; and

in response to the detection, automatically propagate the update to the tenant-specific schema, while the database remains available to accept tenant queries of a tenant corresponding to the tenant-specific schema, without taking the database offline for the update.

18. The system of claim 17 , wherein the system is configured to store data for a tenant according to both the standard schema and the tenant-specific schema for the database object in a non-relational underlying storage format.

19. The system of claim 17 , wherein the instructions are further capable of being executed to:

asynchronously process change records from a change stream, wherein the detection of the update of the standard schema and automatic propagation is based on a change record for the update in the change stream.

20. The system of claim 17 , wherein the standard schema is stored using a top-level scope and the tenant-specific schema is stored in a tenant namespace scope, wherein the instructions are further capable of being executed to:

create the tenant namespace scope and the top-level scope;

configure multitenancy settings for the top-level scope based on one or more commands received via a provisioning application programming interface (API);

update the tenant-specific schema based on one or more commands received via a metadata API; and

update a database object that conforms with the tenant-specific schema based on one or more commands received via a data API.