mysql在5.1之后增加了存储过程的功能, 存储过程运行在mysql内部,语句都已经编译好了,速度比sql更快. 存储过程与mysql相当于shell和linux系统。如果你是程序员的话,那我告诉你存储过程实际上是一个方法,你只要调用这个方法,并且输入它设置好的参数就可以获取或者执行你想要的操作了. 看了如下存储过程实例,你会发现mysql存储过程和shell很像.
下面存储过程内容为:调用存储过程,并且传入用户名,密码参数。存储过程会将这她们存储到process_test表里面.看实例
一,创建数据库
mysql>create database db_proc;
二,创建表
mysql>CREATE TABLE `proc_test` ( `id` tinyint(4) NOT NULL AUTO_INCREMENT, #ID,自动增长 `username` varchar(20) NOT NULL, #用户名 `password` varchar(20) NOT NULL, #密码 PRIMARY KEY (`id`) #主键 ) ENGINE=MyISAM AUTO_INCREMENT=50 DEFAULT CHARSET=utf8; #设置表引擎和字符集
三、创建存储过程
create procedure mytest(in name varchar(20),in pwd varchar(20))#定义传入的参数 begin insert into proc_test(username,password) values(name,pwd); #把传进来的参数name和pwd插入表中,别忘记分号 end; #注意这个分号别忘记了 create procedure mytest(in name varchar(20),in pwd varchar(20))#定义传入的参数 begin insert into proc_test(username,password) values(name,pwd); #把传进来的参数name和pwd插入表中,别忘记分号 end; #注意这个分号别忘记了
四、测试调用存储过程
用法:call 存储过程名称(传入的参数)
call proc_test("绝心是凉白开","www.bitsCN.com")
username为”绝心是凉白开“传入数据库中,密码”www.bitsCN.com“
五、查看数据库中有无加入的数据
select * from proc_test where username=‘绝心是凉白开';#如果有内容说明成功了
六、删除存储过程
drop procdure 存储过程名;
代码如下:
call pr_pager('job j left join enter_job ej on j.job_no=ej.job_no','j.*,ej.*','25','1','group by ej.put_away_user order by ej.put_away_user desc','where j.job_table="enter"',@p_out_rows);
<?php function dump_single_form41report($sys_report_id) { $this->dbConn->setFetchMode(DB_FETCHMODE_ASSOC); //SET @a=1;CALL dbpi_report.simpleproc(@a);SELECT @a; $sql = "CALL dbpi_temp.dumpSingleReportForm41($sys_report_id);"; $result = $this->dbConn->query($sql); if (mysql_error()) { die (mysql_error().'<b>:</b> dump_single_form41report(...)['.__LINE__.'];<br>'.$sql); } return $result; } function initQueuePool($sys_report_id, $username){ $this->dbConn->setFetchMode(DB_FETCHMODE_ASSOC); $this->checkPreviousThread($sys_report_id, $username); $temptablename = "_".$username."_".$sys_report_id; $sql = "SET @a=".$sys_report_id.";"; $this->dbConn->query($sql); $sql = "SET @b='".DB_REPORT.".".$temptablename."';"; $this->dbConn->query($sql); $sql = "SET @c='".DB_PREPRODUCT."';"; $this->dbConn->query($sql); $sql = "CALL ".DB_REPORT.".fm41_simpleproc(@a,@b,@c);"; $this->dbConn->query($sql); }
普通的查询,只返回一个结果集,而存储过程却返回至少两个结果集,其中一个就是存储过程的执行状态。我们必须要清除了这个执行状态以后,才可能再次调用另外一个存储过程 。
<?php $rs=mysql_query("call pr_pager('change_monitor','*',10,1,'','',@p_out_rows)"); while($rows=mysql_fetch_array($rs)){ echo $rows[Schedule]; } $query=mysql_query("select @p_out_rows"); $v=mysql_fetch_array($query); can't return a result set in the given context
需要php调用存储过程,返回一个结果集,发现很困难,找了半天,终于在老外的论坛上找到解决方案,这里本地化一下。
关键就是两点:
1.
define('CLIENT_MULTI_RESULTS', 131072);
2.
$link = mysql_connect("127.0.0.1", "root", "",1,CLIENT_MULTI_RESULTS) or die("Could not connect: ".mysql_error());

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