我做一个成绩管理系统
//学科
$xk = array();
//年级
$nj = array();
//班级
$bj = array();
有三个数组,根据学科*年级*班级这个公式来生成多少条数据,然后写入到数据库。
例如:
count($xk)为2的时候,说明选择了2个学科
count($nj)为3的时候,说明选择了3个年级
count($bj)为7的时候,说明选择了7个年级
这时应该往数据库中插入2*3*7条数据,请问这个该怎么实现呢
回复讨论(解决方案)
php多循环,然后将数据下标循环最后写入数据库,PHP基础差,请求大侠们帮忙
$xk=Array ("1","2");
$nj=Array ("1","2","3");
$bj=Array ("1","2","3","4","5","6","7");
$xk=count($xk);
$nj=count($nj);
$bj=count($bj);
$test="$xk*$nj*$bj";
echo $test;
exit;
?>
晕,理解错了。、
该怎么理解呢
$xk=Array ("1","2");
$nj=Array ("1","2","3");
$bj=Array ("1","2","3","4","5","6","7");
$xk=count($xk);
$nj=count($nj);
$bj=count($bj);
$test="$xk*$nj*$bj";
echo $test;
exit;
?>
我是要生成INSERT INTO语句该怎么写呢
INSERT INTO `examinfo` (`nj`,`bj`,`xk`) VALUES ($nj ,$bj ,$xk),VALUES 后面要插入$xk*$nj*$bj这么多条,该怎么弄呢
到精华区找计算笛卡尔积的代码
写个笨方法。
$xk=Array ("1","2");
$nj=Array ("1","2","3");
$bj=Array ("1","2","3","4","5","6","7");
$arr = array();
for($i=0;$i
}
}
}
foreach($arr as $row){
//插入数据
}
这个有这么复杂嘛,用FOR可以做吗
for($i=0;$i$xk=Array ("1","2");$nj=Array ("1","2","3");$bj=Array ("1","2","3","4","5","6","7");$arr = array();for($i=0;$i<count($xk);$i++){ for($j=0;$j<count($nj);$j++){ for($k=0;$k<count($bj);$k++){ $arr[] = array($xk[$i],$nj[$j],$bj[$k]); } }}foreach($arr as $row){ //插入数据}
写个笨方法。
$xk=Array ("1","2");
$nj=Array ("1","2","3");
$bj=Array ("1","2","3","4","5","6","7");
$arr = array();
for($i=0;$i
}
}
}
foreach($arr as $row){
//插入数据
}
这个好像可行,foreach里面插入数据该怎么写SQL语句呢
$xk=Array ("1","2");$nj=Array ("1","2","3");$bj=Array ("1","2","3","4","5","6","7");$arr = array();for($i=0;$i<count($xk);$i++){ for($j=0;$j<count($nj);$j++){ for($k=0;$k<count($bj);$k++){ $arr[] = array($xk[$i],$nj[$j],$bj[$k]); } }}foreach($arr as $row){ //插入数据}
能不能把 //插入数据 echo一下调用方法。
$xk=Array ("1","2");$nj=Array ("1","2","3");$bj=Array ("1","2","3","4","5","6","7");$arr = array();for($i=0;$i<count($xk);$i++){ for($j=0;$j<count($nj);$j++){ for($k=0;$k<count($bj);$k++){ $arr[] = array($xk[$i],$nj[$j],$bj[$k]); } }}foreach($arr as $row){ //插入数据}
我要的就是这个效果,我要将INSERT INTO `examinfo` (`nj`,`bj`,`xk`) VALUES ($nj ,$bj ,$xk)放到//插入数据的位置,我该怎么写呢。
$xk=Array ("1","2");$nj=Array ("1","2","3");$bj=Array ("1","2","3","4","5","6","7");$arr = array();for($i=0;$i<count($xk);$i++){ for($j=0;$j<count($nj);$j++){ for($k=0;$k<count($bj);$k++){ $arr[] = array($xk[$i],$nj[$j],$bj[$k]); } }}foreach($arr as $row){ $sql = "INSERT INTO `examinfo` (`nj`,`bj`,`xk`) VALUES ('".$row[0]."' ,'".$row[1]."','".$row[2]."')";}
$xk=Array ("1","2");$nj=Array ("1","2","3");$bj=Array ("1","2","3","4","5","6","7");$arr = array();for($i=0;$i<count($xk);$i++){ for($j=0;$j<count($nj);$j++){ for($k=0;$k<count($bj);$k++){ $arr[] = array($xk[$i],$nj[$j],$bj[$k]); } }}foreach($arr as $row){ $sql = "INSERT INTO `examinfo` (`nj`,`bj`,`xk`) VALUES ('".$row[0]."' ,'".$row[1]."','".$row[2]."')";}
非常感谢,但这SQL语句能做点优化最好了,INSERT INTO `examinfo` (`nj`,`bj`,`xk`) VALUES ($nj ,$bj ,$xk)一直是这句在循环,如果做成INSERT INTO `examinfo` (`nj`,`bj`,`xk`) VALUES (1 ,1 ,1),(1 ,1 ,2),(1 ,1 ,3)这样的SQL语句的话就完美了。
晕咯。哥们,你想实现怎么不自己想想呢。不能指望别人什么都给你做好,别人只能给你思路啊。。
晕咯。哥们,你想实现怎么不自己想想呢。不能指望别人什么都给你做好,别人只能给你思路啊。。
嗯,有这个思路,我可以继续往下做了,谢谢,优化的事我有思路了,谢谢了

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