数据库为MySQL（原SQLServer + MySQL）涉及S表、P表、J表及SPJ关系 ---- 第一篇～

      CREATE TABLE S(
    		SNO CHAR(2)PRIMARY KEY,
    		SNAME CHAR(6),
    		STATUS SMALLINT,
    		CITY CHAR(4)
      );
     
    	 CREATE TABLE P (
    			PNO CHAR(2) PRIMARY KEY,
    			PNAME VARCHAR(10),
    			COLOR CHAR(2),
    			WEIGHT SMALLINT
    	 );
    	
    	CREATE TABLE J(
    		JNO CHAR(2)PRIMARY KEY,
    		JNAME CHAR(10),
    		CITY  CHAR(4)
      );
    	
    	
    	CREATE TABLE SPJ(
    		SNO CHAR(2),
    		PNO CHAR(2),
    		JNO CHAR(2),
    		QTY SMALLINT,
    		PRIMARY KEY(SNO,PNO,JNO),
    		FOREIGN KEY(SNO)REFERENCES S(SNO),
    		FOREIGN KEY(PNO)REFERENCES