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Work with memory-optimized system-versioned temporal tables

Applies to: SQL Server 2016 (13.x) and later versions Azure SQL Managed Instance

This article describes how working with a memory-optimized system-versioned temporal table differs from working with a disk-based system-versioned temporal table.

Note

Memory-optimized temporal tables are only available in SQL Server and Azure SQL Managed Instance. Memory-optimized tables and temporal tables are independently available in Azure SQL Database.

Discover metadata

To discover metadata about a memory-optimized system-versioned temporal table, combine information from sys.tables and sys.internal_tables. A system-versioned temporal table appears as the parent_object_id column of the internal in-memory history table.

This example shows how to query and join these tables.

SELECT SCHEMA_NAME(T1.schema_id) AS TemporalTableSchema,
       OBJECT_NAME(IT.parent_object_id) AS TemporalTableName,
       T1.object_id AS TemporalTableObjectId,
       IT.Name AS InternalHistoryStagingName,
       SCHEMA_NAME(T2.schema_id) AS HistoryTableSchema,
       OBJECT_NAME(T1.history_table_id) AS HistoryTableName
FROM sys.internal_tables AS IT
     INNER JOIN sys.tables AS T1
         ON IT.parent_object_id = T1.object_id
     INNER JOIN sys.tables AS T2
         ON T1.history_table_id = T2.object_id
WHERE T1.is_memory_optimized = 1
      AND T1.temporal_type = 2;

Modify data

You can modify memory-optimized temporal tables through natively compiled stored procedures. These procedures let you convert non-temporal memory-optimized tables and keep existing natively stored procedures.

This example shows how to modify an existing table in a natively compiled module.

CREATE PROCEDURE dbo.UpdateFXCurrencyPair (
    @ProviderID INT,
    @CurrencyID1 INT,
    @CurrencyID2 INT,
    @BidRate DECIMAL (8, 4),
    @AskRate DECIMAL (8, 4)
)
WITH NATIVE_COMPILATION,
     SCHEMABINDING,
     EXECUTE AS OWNER
AS
BEGIN ATOMIC
WITH (TRANSACTION ISOLATION LEVEL = SNAPSHOT, LANGUAGE = N'English')
    UPDATE dbo.FXCurrencyPairs
        SET AskRate = @AskRate,
            BidRate = @BidRate
    WHERE ProviderID = @ProviderID
          AND CurrencyID1 = @CurrencyID1
          AND CurrencyID2 = @CurrencyID2;
END;

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