Question

这是Microsoft SQL Server的T-SQL上的有效语法，但在SQLite中没有，是否有另一种语法在SQLite中执行相同的操作？

DELETE FROM something
FROM something
INNER JOIN combinations ON something.field1=combinations.field1
AND something.field2=combinations.field2
--optionally more criteria and/or more joins
WHERE combinations.field3=1234
--or anything really, just to show some criteria could be applied here also

Answer 1

在这里你有另一种选择：

DELETE FROM slave
where slave.master_id in (select master.id from master where master.something=1234)

Answer 2

在一般情况下，将整个联接移动到子查询中，该子查询查找要删除的行的主键：

DELETE FROM something
WHERE id IN (SELECT something.id
             FROM something
             JOIN combinations ON something.field1=combinations.field1
                              AND something.field2=combinations.field2
             WHERE combinations.something=1234)

如果您有复合主键，则可以改为使用rowid：

DELETE FROM something
WHERE rowid IN (SELECT something.rowid
                FROM something
                JOIN combinations ON something.field1=combinations.field1
                                 AND something.field2=combinations.field2
                WHERE combinations.something=1234)

如果您有复合主键并且您将表创建为WITHOUT ROWID表，则必须将连接重写为相关子查询：

DELETE FROM something
WHERE EXISTS (SELECT 1
              FROM combinations
              WHERE field1 = something.field1
                AND field2 = something.field2
                AND field3 = 1234)

SQLite支持＆＃34;从＆＃34;删除

2 个答案: