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我创建了一个带有 2 个主键的表，当我尝试一次删除几条记录时，但整个表都被擦除了。这是我尝试过的代码，我不确定它为什么会这样做。任何帮助都将受到欢迎。

BEGIN TRANSACTION;
DROP TABLE NAMES1;
/* Create a table called NAMES1 */
CREATE TABLE NAMES1(Id integer, Id2 integer, Name text,PRIMARY KEY(Id,Id2));

/* Create few records in this table */
INSERT INTO NAMES1 VALUES(1,1,'Tom');
INSERT INTO NAMES1 VALUES(2,1,'Lucy');
INSERT INTO NAMES1 VALUES(3,4,'Frank');
INSERT INTO NAMES1 VALUES(4,1,'Jane');
INSERT INTO NAMES1 VALUES(5,6,'Robert');
COMMIT;

/* Display all the records from the table */

SELECT Count(*) FROM NAMES1; /* Returns 5 */
DELETE FROM NAMES1 WHERE (Id AND Id2) in ((2 AND 2),(1 AND 1),(2 AND 1));
SELECT Count(*) FROM NAMES1; /* Returns 0 */

根据我的计算，返回的计数应该是 3，而不是 0。

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2 回答 2

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在 SQLite 中，您不能将多个值与单个表达式进行比较。

删除多条记录最简单的方法就是一条一条地删除：

BEGIN;
DELETE FROM Names1 WHERE Id = 2 AND Id2 = 2;
DELETE FROM Names1 WHERE Id = 1 AND Id2 = 1;
DELETE FROM Names1 WHERE Id = 2 AND Id2 = 1;
COMMIT;

或者，编写一个明确检查所有三种组合的条件：

DELETE FROM Names1
WHERE (Id = 2 AND Id2 = 2)
   OR (Id = 1 AND Id2 = 1)
   OR (Id = 2 AND Id2 = 1);
于 2014-06-12T16:52:57.620 回答
-1

该行：

DELETE FROM NAMES1 WHERE (Id AND Id2) in ((2 AND 2),(1 AND 1),(2 AND 1));

相当于：

DELETE FROM NAMES1 WHERE 1 in ((1,1,1);

并删除整个表

将其更改为：

DELETE FROM NAMES1 WHERE Id in (2,1) AND Id2 in (2,1);
于 2014-06-12T16:05:28.760 回答