retrieve data from multiple tables referencing some tables in mysql
i have 10 tables have innoDB engine
1. one is state_table
which attributes are state_id
and state_name
2. another table city_table
which attributes are city_id
and city_name
3. one more table permit_table
which attribute is p_id
above city_id,state_id and permit_id
is references to rest of 7 tables.
each table having state_id, city_id and permit_id referencing above tables
now i want to extract all tables data with their respective city name and state name ( each tables may have different city id and state id)
i m using below mysql query( i know it's very length way.... ) . please tell me how to do it with optimized method?
SELECT p.*,cp.city_name,sp.state_name,
o.*,co.city_name,so.state_name,
t.*,ct.city_name,st.state_name,
............................
.......so on................
............................
FROM permit_table p
JOIN table_city cp ON cp.city_id=p.city_id
JOIN table_state sp ON sp.state_id=p.state_id
JOIN table_one o ON o.permit_id=p.permit_id
JOIN table_city co ON co.city_id=o.city_id
JOIN table_state so ON so.state_id=o.state_id
JOIN table_two t ON t.permit_id=p.permit_id
JOIN table_city ct ON ct.city_id=t.city_id
JOIN table_state st ON st.state_id=t.state_id
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................so on.........................
..............................................
WHERE p.permit_id=base64_encode(mysql_real_escape_string($_GET[pid]));
Thanks to all for helping me always.
Don't think of the tables as having to join EACH OTHER. They just have to join the conglomeration. So rather than adding the "JOIN table_city" and "JOIN table_state" so many times, just make sure that the earlier joins are correct, and when necessary join through the others. For example, you can say
JOIN table_two ON t.permit_id = p.permit_id AND t.city_id = p.city_id AND ...
If the tables do not map to each other directly I'm assuming you must have an intermediary table that will connect the two. If not, it may be useful to make another table where you can map state and city. Depending on what information you are keeping, you can also join tables on something other than the primary key. like if you keep the state name in the city table you can join tables on that too.
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