Important Points About SQL MERGE Statement

MERGE Statement in SQL

MERGE statement in SQL is used to perform insert, update, and delete operations on a target table based on the results of JOIN with a source table. This allows users to synchronize two tables by performing operations on one table based on results from the second table....

Syntax

MERGE INTO target_tableUSING source_tableON merge_conditionWHEN MATCHED THEN   UPDATE SET column1 = value1 [, column2 = value2 …]WHEN NOT MATCHED THEN   INSERT (column1 [, column2 …])   VALUES (value1 [, value2 …]);...

SQL MERGE Statement Example

Suppose there are two tables:...

Important Points About SQL MERGE Statement

The SQL MERGE statement combines INSERT, UPDATE, and DELETE operations into a single statement, allowing for efficient data synchronization between source and target tables.It provides flexibility in customizing complex SQL scripts by handling multiple data manipulation operations in a single transaction.The SQL MERGE statement is commonly used in scenarios like maintaining Slowly Changing Dimensions (SCD) in data warehouses.Proper indexing, optimized join conditions, and filtering the source table for necessary records can optimize the performance of the MERGE statement....