MySQL数据库程序设计套题②【真题截图+原理解析】

建议使用iPad或者网页版浏览

需占据物理空间，不存储在内存；一个表可以有多个索引，但只能有一个聚簇索引，只有唯一性索引要求索引列值不能重复；索引通常可减少表扫描，从而提高检索的效率；

DELIMITER $$
CREATE TRIGGER tri_price BEFORE INSERT ON tb_commodity FOR EACH ROW
  BEGIN
    DECLARE tmp1 CHAR(20);
    DECLARE tmp2 CHAR(20);
    SET tmp1 = NEW.cname;
    SET tmp2 = ________;
    IF (tmp1= '电视机') && (_____= '上海') THEN
      SET ________ = 2800;
  END $$
DELIMITER ;

DELIMITER $$
CREATE PROCEDURE sp_counter(________ ROWS INT)
BEGIN
  DECLARE cid INT;
  DECLARE FOUND BOOLEAN DEFAULT TRUE;
  DECLARE cur_cid CURSOR FOR 
    SELECT cno FROM tb_commodity;
  DECLARE CONTINUE HANDLER FOR NOT FOUND
    SET FOUND=FALSE;
  SET ROWS=0;
  OPEN cur_cid;
  FETCH cur_cid INTO cid;
  WHILE FOUND DO
    SET ROWS=ROWS+1;
    ________ cur_cid INTO cid;
  END WHILE;
  ________ cur_cid;
  END $$
DELIMITER ;

<?php
  $con=mysql_connect("localhost:3306","root","")
    or die("数据库服务器连接失败！<br>");
//**********found**********
  __________("db_mall",$con) or die( "数据库选择失败！<br>");
//**********found**********
  mysql_query("set __________ 'gbk'");
//**********found**********
  $sql="__________ tb_commodity SET price=3888";
//**********found**********
  $sql=$sql." ________ cname='电冰箱' AND origin='武汉'";
//**********found**********
  if (mysql_query(__________,$con)) 
      echo "商品价格修改成功！<br>";
  else
      echo "商品价格修改失败！<br>";
?>