分析一:

$res = M('member')

                    ->table('__MEMBER__ as a')

                    ->join('__ORDER__ as b')

                    ->field('a.id,b.order_sn,count(b.id) as total')

                    ->where('b.receive_member_id = a.id')

                    ->group('a.id')

                    ->order('total desc')

                    ->limit($page->firstRow, $page->listRows)

                    ->select();

1. res=M(′member′),res=M(′member′),res = M('member a') ,$res = M('member as a') 意思相同

2.res = M('member')->table('__MEMBER a')  ,res = M('member')->table('__MEMBER a')  ,res = M('member')->table('__MEMBER as a') 相同

分析二

$res = M('member_attest')

                ->table('__MEMBER_ATTEST__ a')

                ->join('__MEMBER__ b')

                ->join('__ORDER__ c')

                ->field('a.id,a.member_id,a.real_name,a.rank,b.mobile,count(c.id) as total')

                ->where('c.receive_member_id = b.id and  b.id = a.member_id')->group('a.id')

                ->order('total desc')

                ->limit($page->firstRow, $page->listRows)

                ->select();

和

$res = M('member_attest')

                ->table('__MEMBER_ATTEST__ a')

                ->join('__MEMBER__ b ON b.id = a.member_id')

                ->join('__ORDER__ c')

                ->field('a.id,a.member_id,a.real_name,a.rank,b.mobile,count(c.id) as total')

                ->where('c.receive_member_id = b.id')->group('a.id')

                ->order('total desc')

                ->limit($page->firstRow, $page->listRows)

                ->select();

效果一样，join里面也可以不用带 on a.xx=b.xxx ,查询条件可以全部放到where里面

分析三

$res = M('member_attest')

                    ->table('__MEMBER_ATTEST__ a,__MEMBER__ b')

                    ->where('a.member_id = b.id')

                    ->select();

$res = M('member_attest a')

                ->join('__MEMBER__ b')

                ->where('a.member_id = b.id')

                ->select();

$res = M('member_attest a')

                ->join('__MEMBER__ b ON a.member_id = b.id')

                ->select();

这三个都可以正常使用