Spatial Data - sys.dm_db_objects_disabled_on_compatibility_level_change

Стаття
02/28/2023

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

Lists the indexes and constraints that will be disabled as a result of changing compatibility level in SQL Server. Indexes and constraints that contain persisted computed columns whose expressions use spatial UDTs will be disabled after upgrading or changing compatibility level. Use this dynamic management function to determine the impact of a change in compatibility level.

Transact-SQL syntax conventions

Syntax

sys.dm_db_objects_disabled_on_compatibility_level_change ( compatibility_level )

Arguments

compatibility_level
int that identifies the compatibility level that you plan to set.

Table Returned

Column name	Data type	Description
class	int	1 = constraints 7 = indexes and heaps
class_desc	nvarchar(60)	OBJECT or COLUMN for constraints INDEX for indexes and heaps
major_id	int	OBJECT ID of constraints OBJECT ID of table that contains indexes and heaps
minor_id	int	NULL for constraints Index_id for indexes and heaps
dependency	nvarchar(60)	Description of the dependency that is causing the constraint or index to be disabled. The same values are also used in the warnings that are raised during upgrade. Examples include the following: "space" for an intrinsic "geometry" for a system UDT "geography::Parse" for a method of a system UDT

General Remarks

Persisted computed columns that use some intrinsic functions are disabled when the compatibility level is changed. Also, persisted computed columns that use any Geometry or Geography method are disabled when a database is upgraded.

Which functions cause persisted computed columns to be disabled?

When the following functions are used in the expression of a persisted computed column, they cause indexes and constraints that reference those columns to be disabled when the compatibility level is changed from 80 to 90:

IsNumeric

Soundex
Geography:: GeomFromGML
Geography:: STGeomFromText
Geography:: STLineFromText
Geography:: STPolyFromText
Geography:: STMPointFromText
Geography:: STMLineFromText
Geography:: STMPolyFromText
Geography:: STGeomCollFromText
Geography:: STGeomFromWKB
Geography:: STLineFromWKB
Geography:: STPolyFromWKB
Geography:: STMPointFromWKB
Geography:: STMLineFromWKB
Geography:: STMPolyFromWKB
Geography:: STUnion
Geography:: STIntersection
Geography:: STDifference
Geography:: STSymDifference
Geography:: STBuffer
Geography:: BufferWithTolerance
Geography:: Parse
Geography:: Reduce

Behavior of the disabled objects

Indexes

If the clustered index is disabled, or if a nonclustered index is forced, the following error is raised: "The query processor is unable to produce a plan because the index '%.*ls' on table or view '%.*ls' is disabled." To re-enable these objects, rebuild the indexes after upgrade by calling ALTER INDEX ON ... REBUILD.

Heaps

If a table with a disabled heap is used, the following error is raised. To re-enable these objects, rebuild after upgrade by calling ALTER INDEX ALL ON ... REBUILD.

// ErrorNumber: 8674  
// ErrorSeverity: EX_USER  
// ErrorFormat: The query processor is unable to produce a plan because the table or view '%.*ls' is disabled.  
// ErrorCause: The table has a disabled heap.   
// ErrorCorrectiveAction: Rebuild the disabled heap to enable it.   
// ErrorInserts: table or view name   
// ErrorOwner: mtintor   
// ErrorFirstProduct: SQL11

If you try to rebuild the heap during an online operation, an error is raised.

Check Constraints and Foreign Keys

Disabled check constraints and foreign keys do not raise an error. However, the constraints are not enforced when rows are modified. To re-enable these objects, check the constraints after upgrading by calling ALTER TABLE ... CHECK CONSTRAINT.

Persisted Computed Columns

Since it is not possible to disable a single column, the entire table is disabled by disabling the clustered index or heap.

Security

Permissions

Requires the VIEW DATABASE STATE permission.

Permissions for SQL Server 2022 and later

Requires VIEW DATABASE PERFORMANCE STATE permission on the database.

Example

The following example shows a query on sys.dm_db_objects_disabled_on_compatibility_level_change to find the objects impacted by changing the compatibility level to 120.

SELECT * FROM sys.dm_db_objects_disabled_on_compatibility_level_change(120);  
GO

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