使用复合主键删除另一个 table 中不存在的行

Question

我正在使用 SQLite 并尝试将旧行从 table 学生移动到 Students_Old，并从 Students_Import.

复制新行

问题是我有多个主键，如下所示：

CREATE TABLE "Students" (
`LastName`  TEXT NOT NULL,
`FirstName` TEXT NOT NULL,
`BornDate`  TEXT NOT NULL,
`Class` TEXT NOT NULL,
`Photo` TEXT,
`ValidUntil`    CHAR(10),
PRIMARY KEY(LastName,FirstName,BornDate))

所有 table 都具有此结构（Students_Import 除外，它缺少 Photo 和 ValidUntil）。

到目前为止，我已经成功地复制了旧行：

INSERT INTO Students_Old 
SELECT DISTINCT a.LastName, a.FirstName, a.BornDate, a.Class, a.Photo, a.ValidUntil FROM
Students a LEFT JOIN Students_Import b ON a.LastName =b.LastName AND a.FirstName=b.FirstName AND a.BornDate=b.BornDate WHERE b.LastName is NULL;

并添加新行：

INSERT INTO Students 
SELECT DISTINCT a.LastName, a.FirstName, a.BornDate, a.Class, "", "" FROM 
Students_Import a LEFT JOIN Students b ON a.LastName =b.LastName AND a.FirstName=b.FirstName AND a.BornDate=b.BornDate WHERE b.LastName is NULL

但我不知道如何删除学生中的旧行（Students_Import 中不存在）。

我试过几个变体：

DELETE FROM Students WHERE (LastName, FirstName, BornDate) IN
(SELECT DISTINCT a.LastName, a.FirstName, a.BornDate, a.Class, a.Photo, a.ValidUntil FROM 
Students a LEFT JOIN Students_Import b ON a.LastName =b.LastName AND a.FirstName=b.FirstName AND a.BornDate=b.BornDate WHERE b.LastName is NULL);

但我只收到语法错误，或者我无法在多行上使用它。

如有任何帮助，我将不胜感激！

Answer 1

我认为您不能在 IN 子句中包含多个列。

怎么样： DELETE Students FROM Students s LEFT JOIN Students_Import si ON (s.LastName = si.LastName AND s.FirstName = si.FirstName AND s.BornDate = si.BornDate) WHERE s.LastName IS NULL;

Answer 2

IN 不适用于多列。

要查找另一个 table 中不存在的行，请使用 NOT EXISTS 和 correlated subquery:

DELETE FROM Students
WHERE NOT EXISTS (SELECT 1
                  FROM Students_Import
                  WHERE Students_Import.LastName  = Students.LastName
                    AND Students_Import.FirstName = Students.FirstName
                    AND Students_Import.BornDate  = Students.BornDate);

使用复合主键删除另一个 table 中不存在的行

Deleting rows not existing in another table with composite primary key's

sqlite

composite-primary-key

sql-delete