SQL MERGE Statement Guide

There is no built-in MERGE function in SQL, but you can achieve similar functionality using the MERGE statement. The MERGE statement is used to determine if data exists based on specified conditions, and if it does, update the data, or insert it if it doesn’t.

The basic syntax of a MERGE statement is as follows:

MERGE INTO target_table USING source_table
ON merge_condition
WHEN MATCHED THEN
    UPDATE SET column1 = value1, column2 = value2,...
WHEN NOT MATCHED THEN
    INSERT (column1, column2,...) VALUES (value1, value2,...);

target_table is the table where the data will be updated or inserted, source_table is the table containing the data to be updated or inserted, merge_condition is the condition used to match the target table and source table, UPDATE SET clause is used to specify the columns and values to be updated, INSERT clause is used to specify the columns and values to be inserted.

With the MERGE statement, it is easy to update or insert data based on conditions, avoiding the need for multiple queries and updates on the target table.