MERGE INTO target_table USING source_table
    ON target_table.id = source_table.id
    WHEN MATCHED THEN
        UPDATE SET target_table.description = source_table.description;
--------------------
MERGE INTO target_table
USING source_table ON target_table.id = source_table.id
WHEN MATCHED THEN UPDATE
SET target_table.description = source_table.description;
------------------------------------------------------------------------------------------------------------------------
CREATE TABLE target_table (ID INTEGER, description VARCHAR);
--------------------
CREATE TABLE target_table (
	ID INTEGER,
	description VARCHAR
);