j2.sql

数据库方面的知识 最基本的建表

SELECT DISTINCT SNO
FROM SPJ
WHERE JNO='J1';
SELECT DISTINCT SNO
FROM SPJ
WHERE JNO='J1'AND PNO='P1';
SELECT DISTINCT SNO
FROM P,SPJ
WHERE  P.COLOR='红'AND SPJ.PNO=P.PNO AND SPJ.JNO='J1';