SQL Update语句是用来更新数据库表中的记录的，常见的写法有以下几种：
UPDATE table_name
SET column_name = new_value
WHERE condition;
UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;
UPDATE table_name
SET column_name = (SELECT new_value FROM another_table WHERE condition)
WHERE condition;
UPDATE table_name
SET column_name = CASE
WHEN condition1 THEN value1
WHEN condition2 THEN value2
ELSE default_value
END
WHERE condition;
UPDATE table1
JOIN table2 ON table1.id = table2.id
SET table1.column_name = table2.new_value
WHERE condition;
以上是SQL Update语句的常见写法，根据实际需求选择合适的方法来更新数据库表中的记录。
