Solving a SQL solution

Source: Internet
Author: User
Solve a SQL
Suppose there are three tables below.
Ta
TA_ID (primary key) Ta_name Ta_cont Ta_typeid

Tb
TB_ID (primary key) Tb_taid Tb_cont

Tc
TC_ID (primary key) Tc_tatypeid Tc_type

Where Tb_taid corresponds to ta_id,tc_tatypeid corresponding to Ta_typeid, now a SQL out Ta_name,ta_cont,count (tb_taid), tc_type how to write

That's what I wrote, but no, count (tb_taid) as com goes out the count of all the IDs, not the count of each ta_id, how do I write

Select Ta_name,ta_cont,count (tb_taid) as Com,tc_type from TA left join TB on Ta_id=tb_taid LEFT join TC on TA_TYPEID=TC_TA typeID ORDER BY ta_id Desc;

------Solution--------------------
You don't have to assign a group key, and you don't get the right results.
------Solution--------------------

Select Ta_name,ta_cont,count (tb_taid) as Com,tc_type from TA left join TB on Ta_id=tb_taid LEFT join TC on TA_TYPEID=TC_TA typeID GROUP by Ta_cont ORDER by ta_id Desc;

This kind of naming makes people look dizzy. In short, use GROUP by =_= ...
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