Transact-SQL Constructs Not Supported by In-Memory OLTP

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

Memory-optimized tables, natively compiled stored procedures, and user-defined functions do not support the full Transact-SQL surface area that is supported by disk-based tables, interpreted Transact-SQL stored procedures, and user-defined functions. When attempting to use one of the unsupported features, the server returns an error.

The error message text mentions the type of Transact-SQL statement (feature, operation, option, for example) and well as the name of the feature or Transact-SQL keyword. Most unsupported features will return error 10794, with the error message text indicating the unsupported feature. The following tables list the Transact-SQL features and keywords that can appear in the error message text, as well as the corrective action to resolve the error.

For more information on supported features with memory-optimized tables and natively compiled stored procedures, see:

Databases That Use In-Memory OLTP

The following table lists the Transact-SQL features that are not supported, and the keywords that can appear in the message text of an error involving an In-Memory OLTP database. The table also lists the resolution for the error.

Type Name Resolution
Option AUTO_CLOSE The database option AUTO_CLOSE=ON is not supported with databases that have a MEMORY_OPTIMIZED_DATA filegroup.
Option ATTACH_REBUILD_LOG The CREATE database option ATTACH_REBUILD_LOG is not supported with databases that have a MEMORY_OPTIMIZED_DATA filegroup.
Feature DATABASE SNAPSHOT Creating database snapshots is not supported with databases that have a MEMORY_OPTIMIZED_DATA filegroup.
Feature Replication using the sync_method 'database snapshot' or 'database snapshot character' Replication using the sync_method 'database snapshot' or 'database snapshot character' is not supported with databases that have a MEMORY_OPTIMIZED_DATA filegroup.
Feature DBCC CHECKDB

DBCC CHECKTABLE
DBCC CHECKDB skips the memory-optimized tables in the database.

DBCC CHECKTABLE will fail for memory-optimized tables.

Memory-Optimized Tables

The following table lists the Transact-SQL features that are not supported, and the keywords that can appear in the message text of an error involving a memory-optimized table. The table also lists the resolution for the error.

Type Name Resolution
Feature ON Memory-optimized tables cannot be placed on a filegroup or partition scheme. Remove the ON clause from the CREATE TABLE statement.

All memory optimized tables are mapped to memory-optimized filegroup.
Data type Data type name The indicated data type is not supported. Replace the type with one of the supported data types. For more information, see Supported Data Types for In-Memory OLTP.
Feature Computed columns Applies to: SQL Server 2014 (12.x) and SQL Server 2016 (13.x)
Computed columns are not supported for memory-optimized tables. Remove the computed columns from the CREATE TABLE statement.

Azure SQL Database and SQL Server starting SQL Server 2017 (14.x) do support computed columns in memory-optimized tables and indexes.
Feature Replication Replication is not supported with memory-optimized tables.
Feature FILESTREAM FILESTREAM storage is not supported columns of memory-optimized tables. Remove the FILESTREAM keyword from the column definition.
Feature SPARSE Columns of memory-optimized tables cannot be defined as SPARSE. Remove the SPARSE keyword from the column definition.
Feature ROWGUIDCOL The option ROWGUIDCOL is not supported for columns of memory-optimized tables. Remove the ROWGUIDCOL keyword from the column definition.
Feature FOREIGN KEY Applies to: Azure SQL Database and SQL Server starting SQL Server 2016 (13.x)
For memory-optimized tables, FOREIGN KEY constraints are only supported for foreign keys referencing primary keys of other memory-optimized tables. Remove the constraint from the table definition if the foreign key references a unique constraint.

In SQL Server 2014 (12.x), FOREIGN KEY constraints are not supported with memory-optimized tables.
Feature clustered index Specify a nonclustered index. In the case of a primary key index be sure to specify PRIMARY KEY NONCLUSTERED.
Feature DDL inside transactions Memory-optimized tables and natively compiled stored procedures cannot be created or dropped in the context of a user transaction. Do not start a transaction and ensure the session setting IMPLICIT_TRANSACTIONS is OFF before executing the CREATE or DROP statement.
Feature DDL triggers Memory-optimized tables and natively compiled stored procedures cannot be created or dropped if there is a server or database trigger for that DDL operation. Remove the server and database triggers on CREATE/DROP TABLE and CREATE/DROP PROCEDURE.
Feature EVENT NOTIFICATION Memory-optimized tables and natively compiled stored procedures cannot be created or dropped if there is a server or database event notification for that DDL operation. Remove the server and database event notifications on CREATE TABLE or DROP TABLE and CREATE PROCEDURE or DROP PROCEDURE.
Feature FileTable Memory-optimized tables cannot be created as file tables. Remove the argument AS FileTable from the CREATE TABLE statement
Operation Update of primary key columns Primary key columns in memory-optimized tables and table types cannot be updated. If the primary key needs to be updated, delete the old row and insert the new row with the updated primary key.
Operation CREATE INDEX Indexes on memory-optimized tables must be specified inline with the CREATE TABLE statement, or with the ALTER TABLE statement.
Operation CREATE FULLTEXT INDEX Fulltext indexes are not supported for memory-optimized tables.
Operation schema change Memory-optimized tables and natively compiled stored procedures do not support certain schema changes:
Azure SQL Database and SQL Server starting SQL Server 2017 (14.x): ALTER TABLE, ALTER PROCEDURE, and sp_rename operations are supported. Other schema changes, for example adding extended properties, are not supported.

SQL Server 2016 (13.x): ALTER TABLE and ALTER PROCEDURE operations are supported. Other schema changes, including sp_rename, are not supported.

SQL Server 2014 (12.x): schema changes are not supported. To change the definition of a memory-optimized table or natively compiled stored procedure, first drop the object and then recreate it with the desired definition.
Operation TRUNCATE TABLE The TRUNCATE operation is not supported for memory-optimized tables. To remove all rows from a table, delete all rows using DELETE FROM table or drop and recreate the table.
Operation ALTER AUTHORIZATION Changing the owner of an existing memory-optimized table or natively compiled stored procedure is not supported. Drop and recreate the table or procedure to change ownership.
Operation ALTER SCHEMA Transferring an existing table or natively compiled stored procedure to another schema is not supported. Drop and recreate the object to transfer between schemas.
Operation DBCC CHECKTABLE DBCC CHECKTABLE are not supported with memory-optimized tables. To verify the integrity of the on-disk checkpoint files, perform a backup of the MEMORY_OPTIMIZED_DATA filegroup.
Feature ANSI_PADDING OFF The session option ANSI_PADDING must be ON when creating memory-optimized tables or natively compiled stored procedures. Execute SET ANSI_PADDING ON before running the CREATE statement.
Option DATA_COMPRESSION Data compression is not supported for memory-optimized tables. Remove the option from the table definition.
Feature DTC Memory-optimized tables and natively compiled stored procedures cannot be accessed from distributed transactions. Use SQL transactions instead.
Operation Memory-optimized tables as target of MERGE Memory-optimized tables cannot be the target of a MERGE operation. Use INSERT, UPDATE, and DELETE statements instead.

Indexes on Memory-Optimized Tables

The following table lists the Transact-SQL features and keywords that can appear in the message text of an error involving an index on a memory-optimized table, as well as the corrective action to resolve the error.

Type Name Resolution
Feature Filtered index Filtered indexes are not supported with memory-optimized tables. Omit the WHERE clause from the index specification.
Feature Included columns Specifying included columns is not necessary for memory-optimized tables. All columns of the memory-optimized table are implicitly included in every memory-optimized index.
Operation DROP INDEX Dropping indexes on memory-optimized tables is not supported. You can delete indexes using ALTER TABLE.

For more information, see Altering Memory-Optimized Tables.
Index option Index option Only one index option is supported - BUCKET_COUNT for HASH indexes.

Nonclustered Hash Indexes

The following table lists the Transact-SQL features and keywords that can appear in the message text of an error involving a nonclustered hash index, as well as the corrective action to resolve the error.

Type Name Resolution
Option ASC/DESC Nonclustered hash indexes are not ordered. Remove the keywords ASC and DESC from the index key specification.

Natively Compiled Stored Procedures and User-Defined Functions

The following table lists the Transact-SQL features and keywords that can appear in the message text of an error involving natively compiled stored procedures and user-defined functions, as well as the corrective action to resolve the error.

Type Feature Resolution
Feature Inline table variables Table types cannot be declared inline with variable declarations. Table types must be declared explicitly using a CREATE TYPE statement.
Feature Cursors Cursors are not supported on or in natively compiled stored procedures.

When executing the procedure from the client, use RPC rather than the cursor API. With ODBC, avoid the Transact-SQL statement EXECUTE, instead specify the name of the procedure directly.

When executing the procedure from a Transact-SQL batch or another stored procedure, avoid using a cursor with the natively compiled stored procedure.

When creating a natively compiled stored procedure, rather than using a cursor, use set-based logic or a WHILE loop.
Feature Non-constant parameter defaults When using default values with parameters on natively compiled stored procedures, the values must be constants. Remove any wildcards from the parameter declarations.
Feature EXTERNAL CLR stored procedures cannot be natively compiled. Either remove the AS EXTERNAL clause or the NATIVE_COMPILATION option from the CREATE PROCEDURE statement.
Feature Numbered stored procedures Natively compiled stored procedures cannot be numbered. Remove the ;number from the CREATE PROCEDURE statement.
Feature multi-row INSERT ... VALUES statements Cannot insert multiple rows using the same INSERT statement in a natively compiled stored procedure. Create INSERT statements for each row.
Feature Common Table Expressions (CTEs) Common table expressions (CTE) are not supported in natively compiled stored procedures. Rewrite the query.
Feature COMPUTE The COMPUTE clause is not supported. Remove it from the query.
Feature SELECT INTO The INTO clause is not supported with the SELECT statement. Rewrite the query as INSERT INTO Table SELECT.
Feature incomplete insert column list In general, in INSERT statements values must be specified for all columns in the table.

However, we do support DEFAULT constraints and IDENTITY(1,1) columns on memory optimized tables. These columns can be, and in the case of IDENTITY columns must be, omitted from the INSERT column list.
Feature Function Some built-in functions are not supported in natively compiled stored procedures. Remove the rejected function from the stored procedure. For more information about supported built-in functions, see
Supported Features for Natively Compiled T-SQL Modules, or
Natively Compiled Stored Procedures.
Feature CASE Applies to: SQL Server 2014 (12.x) and SQL Server starting SQL Server 2016 (13.x)
CASE expressions are not supported in queries inside natively compiled stored procedures. Create queries for each case. For more information, see Implementing a CASE Expression in a Natively Compiled Stored Procedure.

Azure SQL Database and SQL Server starting SQL Server 2017 (14.x) do support CASE expressions.
Feature INSERT EXECUTE Remove the reference.
Feature EXECUTE Supported only to execute natively compiled stored procedures and user-defined functions.
Feature user-defined aggregates User-defined aggregate functions cannot be used in natively compiled stored procedures. Remove the reference to the function from the procedure.
Feature browse mode metadata Natively compiled stored procedures do not support browse mode metadata. Make sure the session option NO_BROWSETABLE is set to OFF.
Feature DELETE with FROM clause The FROM clause is not supported for DELETE statements with a table source in natively compiled stored procedures.

DELETE with the FROM clause is supported when it is used to indicate the table to delete from.
Feature UPDATE with FROM clause The FROM clause is not supported for UPDATE statements in natively compiled stored procedures.
Feature temporary procedures Temporary stored procedures cannot be natively compiled. Either create a permanent natively compiled stored procedure or a temporary interpreted Transact-SQL stored procedure.
Isolation level READ UNCOMMITTED The isolation level READ UNCOMMITTED is not supported for natively compiled stored procedures. Use a supported isolation level, such as SNAPSHOT.
Isolation level READ COMMITTED The isolation level READ COMMITTED is not supported for natively compiled stored procedures. Use a supported isolation level, such as SNAPSHOT.
Feature temporary tables Tables in tempdb cannot be used in natively compiled stored procedures. Instead, use a table variable or a memory-optimized table with DURABILITY=SCHEMA_ONLY.
Feature DTC Memory-optimized tables and natively compiled stored procedures cannot be accessed from distributed transactions. Use SQL transactions instead.
Feature EXECUTE WITH RECOMPILE The option WITH RECOMPILE is not supported for natively compiled stored procedures.
Feature Execution from the dedicated administrator connection. Natively compiled stored procedures cannot be executed from the dedicated admin connection (DAC). Use a regular connection instead.
Operation savepoint Natively compiled stored procedures cannot be invoked from transactions that have an active savepoint. Remove the savepoint from the transaction.
Operation ALTER AUTHORIZATION Changing the owner of an existing memory-optimized table or natively compiled stored procedure is not supported. Drop and recreate the table or procedure to change ownership.
Operator OPENROWSET This operator is not supported. Remove OPENROWSET from the natively compiled stored procedure.
Operator OPENQUERY This operator is not supported. Remove OPENQUERY from the natively compiled stored procedure.
Operator OPENDATASOURCE This operator is not supported. Remove OPENDATASOURCE from the natively compiled stored procedure.
Operator OPENXML This operator is not supported. Remove OPENXML from the natively compiled stored procedure.
Operator CONTAINSTABLE This operator is not supported. Remove CONTAINSTABLE from the natively compiled stored procedure.
Operator FREETEXTTABLE This operator is not supported. Remove FREETEXTTABLE from the natively compiled stored procedure.
Feature table-valued functions Table-valued functions cannot be referenced from natively compiled stored procedures. One possible workaround for this restriction is to add the logic in the table-valued functions to the procedure body.
Operator CHANGETABLE This operator is not supported. Remove CHANGETABLE from the natively compiled stored procedure.
Operator GOTO This operator is not supported. Use other procedural constructs such as WHILE.
Operator OFFSET This operator is not supported. Remove OFFSET from the natively compiled stored procedure.
Operator INTERSECT This operator is not supported. Remove INTERSECT from the natively compiled stored procedure. In some cases an INNER JOIN can be used to obtain the same result.
Operator EXCEPT This operator is not supported. Remove EXCEPT from the natively compiled stored procedure.
Operator APPLY Applies to: SQL Server 2014 (12.x) and SQL Server starting SQL Server 2016 (13.x)
This operator is not supported. Remove APPLY from the natively compiled stored procedure.

Azure SQL Database and SQL Server starting SQL Server 2017 (14.x) do support the APPLY operator in natively compiled modules.
Operator PIVOT This operator is not supported. Remove PIVOT from the natively compiled stored procedure.
Operator UNPIVOT This operator is not supported. Remove UNPIVOT from the natively compiled stored procedure.
Operator CONTAINS This operator is not supported. Remove CONTAINS from the natively compiled stored procedure.
Operator FREETEXT This operator is not supported. Remove FREETEXT from the natively compiled stored procedure.
Operator TSEQUAL This operator is not supported. Remove TSEQUAL from the natively compiled stored procedure.
Operator LIKE This operator is not supported. Remove LIKE from the natively compiled stored procedure.
Operator NEXT VALUE FOR Sequences cannot be referenced inside natively compiled stored procedures. Obtain the value using interpreted Transact-SQL, and then pass it into the natively compiled stored procedure. For more information, see Implementing IDENTITY in a Memory-Optimized Table.
Set option option SET options cannot be changed inside natively compiled stored procedures. Certain options can be set with the BEGIN ATOMIC statement. For more information, see the section on atomic blocks in Natively Compiled Stored Procedures.
Operand TABLESAMPLE This operator is not supported. Remove TABLESAMPLE from the natively compiled stored procedure.
Option RECOMPILE Natively compiled stored procedures are compiled at create time. Remove RECOMPILE from the procedure definition.

You can execute sp_recompile on a natively compiled stored procedure, which causes it to recompile on the next execution.
Option ENCRYPTION This option is not supported. Remove ENCRYPTION from the procedure definition.
Option FOR REPLICATION Natively compiled stored procedures cannot be created for replication. Removed FOR REPLICATION from the procedure definition.
Option FOR XML This option is not supported. Remove FOR XML from the natively compiled stored procedure.
Option FOR BROWSE This option is not supported. Remove FOR BROWSE from the natively compiled stored procedure.
Join hint HASH, MERGE Natively compiled stored procedures only support nested-loops joins. Hash and merge joins are not supported. Remove the join hint.
Query hint Query hint This query hint is not inside natively compiled stored procedures. For supported query hints see Query Hints (Transact-SQL).
Option PERCENT This option is not supported with TOP clauses. Remove PERCENT from the query in the natively compiled stored procedure.
Option WITH TIES Applies to: SQL Server 2014 (12.x) and SQL Server 2016 (13.x)
This option is not supported with TOP clauses. Remove WITH TIES from the query in the natively compiled stored procedure.

Azure SQL Database and SQL Server starting SQL Server 2017 (14.x) do support TOP WITH TIES.
Aggregate function Aggregate function Not all aggregate functions are supported. For more information about supported aggregate functions in natively compiled T-SQL modules, see Supported Features for Natively Compiled T-SQL Modules.
Ranking function Ranking function Ranking functions are not supported in natively compiled stored procedures. Remove them from the procedure definition.
Function Function This function is not supported. For more information about supported functions in natively compiled T-SQL modules, see Supported Features for Natively Compiled T-SQL Modules.
Statement Statement This statement is not supported. For more information about supported functions in natively compiled T-SQL modules, see Supported Features for Natively Compiled T-SQL Modules.
Feature MIN and MAX used with binary and character strings The aggregate functions MIN and MAX cannot be used for character and binary string values inside natively compiled stored procedures.
Feature GROUP BY ALL ALL cannot be used with GROUP BY clauses in natively compiled stored procedures. Remove ALL from the GROUP BY clause.
Feature GROUP BY () Grouping by an empty list is not supported. Either remove the GROUP BY clause, or include columns in the grouping list.
Feature ROLLUP ROLLUP cannot be used with GROUP BY clauses in natively compiled stored procedures. Remove ROLLUP from the procedure definition.
Feature CUBE CUBE cannot be used with GROUP BY clauses in natively compiled stored procedures. Remove CUBE from the procedure definition.
Feature GROUPING SETS GROUPING SETS cannot be used with GROUP BY clauses in natively compiled stored procedures. Remove GROUPING SETS from the procedure definition.
Feature BEGIN TRANSACTION, COMMIT TRANSACTION, and ROLLBACK TRANSACTION Use ATOMIC blocks to control transactions and error handling. For more information, see Atomic Blocks.
Feature Inline table variable declarations. Table variables must reference explicitly defined memory-optimized table types. You should create a memory-optimized table type and use that type for the variable declaration, rather than specifying the type inline.
Feature Disk-based tables Disk-based tables cannot be accessed from natively compiled stored procedures. Remove references to disk-based tables from the natively compiled stored procedures. Or, migrate the disk-based table(s) to memory optimized.
Feature Views Views cannot be accessed from natively compiled stored procedures. Instead of views, reference the underlying base tables.
Feature Table valued functions Applies to: Azure SQL Database and SQL Server starting SQL Server 2016 (13.x)
Multi-statement table-valued functions cannot be accessed from natively compiled T-SQL modules. Inline table-valued functions are supported, but must be created WITH NATIVE_COMPILATION.

Applies to: SQL Server 2014 (12.x)
Table-valued functions cannot be referenced from natively compiled T-SQL modules.
Option PRINT Remove reference
Feature DDL No DDL is supported inside natively compiled T-SQL modules.
Option STATISTICS XML Not supported. When you run a query, with STATISTICS XML enabled, the XML content is returned without the part for the natively compiled stored procedure.

Transactions that Access Memory-Optimized Tables

The following table lists the Transact-SQL features and keywords that can appear in the message text of an error involving transactions that access memory-optimized tables, as well as the corrective action to resolve the error.

Type Name Resolution
Feature savepoint Creating explicit savepoints in transactions that access memory-optimized tables is not supported.
Feature bound transaction Bound sessions cannot participate in transactions that access memory-optimized tables. Do not bind the session before executing the procedure.
Feature DTC Transactions that access memory-optimized tables cannot be distributed transactions.

See Also

Migrating to In-Memory OLTP