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WHERE clause in the UPDATE statement. The WHERE clause specifies which record (s) that should be updated. If you omit the WHERE clause, all records in the table will be updated! Demo Database. Below is a selection from the "Customers" table in the Northwind sample database: UPDATE Table.
An UPDATE statement can start with a WITH clause to define common table expressions accessible within the UPDATE. See Section 15.2.20, “WITH (Common Table Expressions)”. Single-table syntax: UPDATE [LOW_PRIORITY] [IGNORE] table_reference . SET assignment_list . [WHERE where_condition] [ORDER BY ...] [LIMIT row_count] value: {expr | DEFAULT}
21 Απρ 2010 · I needed to update several rows in a table at once; started with just finding them: SELECT * FROM some_table WHERE field1 IN (SELECT ...) This returned a selection of about 60 rows.
Third, specify which rows to be updated using a condition in the WHERE clause. The WHERE clause is optional. If you omit it, the UPDATE statement will modify all rows in the table.
The UPDATE statement in MySQL allows you to modify existing rows in a table based on specified conditions. Using the WHERE clause carefully is crucial to ensure only the intended rows are updated. With these examples, you now have a foundational understanding of how to use UPDATE to manage data in MySQL tables effectively.
An UPDATE statement can start with a WITH clause to define common table expressions accessible within the UPDATE. See Section 13.2.15, “WITH (Common Table Expressions)”. Single-table syntax: UPDATE [LOW_PRIORITY] [IGNORE] table_reference . SET assignment_list . [WHERE where_condition] [ORDER BY ...] [LIMIT row_count] value: {expr | DEFAULT}
Notice the WHERE clause in the UPDATE statement. The WHERE clause specifies which record(s) that should be updated. If you omit the WHERE clause, all records in the table will be updated!
