CODEWITHSUNDEEP
mysqlsqljoin
R.B.
R.B.

Reputation: 537

MySQL query - join different tables based on a precondition (value retrieved from a different table)

I have following tables :

1. club_members (id, type, name)
2. male_members (name, age, location)
3. female_members (name, age, location)
4. senior_members (name, age, location)

I need to select 1 of these 3 tables based on type retrieved from 1st table. like for type=male, i will select from male_members and so on.

so i want to write a query similar to 

select type, name , age , location from club_members , (2/3/4 table) where id=X ...

how to write such query.

may be using if/else or case statements

Upvotes: 1

Views: 762

Answers (1)

Prahalad Gaggar
Prahalad Gaggar

Reputation: 11599

Assuming Name as the link between tables.

select 
       C.type as Type,
       COALESCE(m.name, f.name, s.name) AS MemberName, 
       COALESCE(m.age, f.age, s.age) AS MemberAge, 
       COALESCE(m.location, f.location, s.location) AS Location
from club_members C
left join male_members M on C.name=M.name and C.type='Male'
left join female_members F on C.name=F.name and C.type='Female'
left join senior_members S on C.name=S.name and C.type='Senior'
where C.id='Your value'

Upvotes: 4

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