how to view with 3 table

[hasan939]

I have 3 tables
1. dealer(id,phone) --- primary key(id)
2. payment(id,amount) --- foreign key(id) reference dealer(id)
3.sell(id,unit) --- foreign key(id) reference dealer(id)


The dealer table contains----------
id---phone
______________________
1-------11
2-------22
3-------33
4-------44
5-------55

The payment table contains--------
id amount
_______________________
1-------100
2-------200
3-------300
2-------200
3-------300
2-------200


The sell table contains--------
id unit
_______________________
3-------3
4-------4
3-------3
3-------3



I want to make such a sql that return like the following---------

id amount unit
____________________________
1-------100-------0
2-------400-------0
3-------900-------9
4-------0----------4
5-------0--------- 0

Please help me to make the sql.

[pbmods]

Heya, Hasan. Welcome to TSDN!

To do this, you'll want to join two of your tables, probably using a LEFT JOIN; that would make for the most readable code.

You'll also need to use the SUM() aggregate function, which also means that you'll need to GROUP BY `id`.

This should get you started. You're looking at a real meat-and-potatoes situation here. Once you get used to writing this sort of query, it makes 90% of the rest of your job a whole lot easier (or at least the part of it that involves writing queries).