php mysql 用join查询多表联合数据时,如何查询提高查询速度,请各位大神给点建议
昊喵喵博士 2016-08-15 01:56:20 $pj = M('pj as p');
$tea = M('teacher');
$data = array();
/****************************************/
$where["departmentid"] = $departmentid;
$te = $tea->field('name,username as id,departmentid')->where($where)->select();
foreach ($te as $key => $value) {
$teacherid["teacherid"] = $value["id"];
$pjgl = $pj
->field('p.*,tp.name as name,tp.typename,tp.type,tp.roleid,tp.rolename')
->join('testpaper as tp on tp.id=p.testpaperid')
->where($teacherid)
->select();
if (count($pjgl)>0){
$value["children"] = $pjgl;
$data[] = $value;
}
}
$this->ajaxReturn($data);