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6 Οκτ 2012 · UPDATE `table` SET uid = CASE id WHEN 10 THEN 2952 WHEN 20 THEN 4925 WHEN 30 THEN 1592 END CASE WHERE id IN (10, 20, 30) or the simpler: UPDATE `table` SET uid = ELT(FIELD(id, 10, 20, 30), 2952, 4925, 1592) WHERE id IN (10, 20, 30) As FIELD() returns the index (position) of str in the str1, str2, str3, ... list. Returns 0 if str is not found.
30 Ιουλ 2019 · For using MySQL CASE statement while using UPDATE Query, you can use CASE statement. Let us first create a table − mysql> create table DemoTable ( UserId int NOT NULL AUTO_INCREMENT PRIMARY KEY, UserScore int ); Query OK, 0 rows affected (0.29 sec)
The MySQL UPDATE Statement. The UPDATE statement is used to modify the existing records in a table. UPDATE Syntax. UPDATE table_name. SET column1 = value1, column2 = value2, ... WHERE condition; Note: Be careful when updating records in a table! Notice the . WHERE clause in the UPDATE statement.
UPDATE is a DML statement that modifies rows in a 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]
MySQL CASE expression is a control flow structure that allows you to add if-else logic to a query. Generally speaking, you can use the CASE expression anywhere that allows a valid expression e.g., SELECT, WHERE and ORDER BY clauses. The CASE expression has two forms: simple CASE and searched CASE.
The MySQL CASE Statement. The CASE statement goes through conditions and returns a value when the first condition is met (like an if-then-else statement). So, once a condition is true, it will stop reading and return the result. If no conditions are true, it returns the value in the ELSE clause.
1 Φεβ 2010 · Here's a query to update a table based on a comparison of another table. If record is not found in tableB, it will update the "active" value to "n". If it's found, will set the value to NULL. UPDATE tableA LEFT JOIN tableB ON tableA.id = tableB.id SET active = IF(tableB.id IS NULL, 'n', NULL)"; Hope this helps someone else.
