Rewrite query with EXISTS clause

xmasam · #1 (**permalink**) 06-01-04, 06:40

Hi!

I have to rewrite a query with EXISTS clause for MySQL 3.23 since I cannot use MySQL 4.1.
The purpose of the query was to find all records from table MAIN that are annotated by a given set of numbers (number1, number2, ...). I have two tables: MAIN(ID, NAME) and A(ID, NUMBER) that stores the annotation relationship. The original query was:

SELECT NAME FROM MAIN WHERE
EXISTS (SELECT * FROM A WHERE MAIN.ID=A.ID AND NUMBER='number1') AND
EXISTS (SELECT * FROM A WHERE MAIN.ID=A.ID AND NUMBER='number2') AND ... so on for every number.

Is there any other way to write this query? Without the EXISTS clause?

Thanks,
Mike

r937 · #2 (**permalink**) 06-01-04, 08:59

whoever wrote that query was missing something very obvious

Code:

select NAME 
  from MAIN 
inner
  join A
    on MAIN.ID 
     = A.ID 
 where NUMBER
    in ('number1','number2',...)
group
    by NAME

Edit: ooops those were ANDs joining the EXISTs clauses, not ORs

okay, forget the above, use this:

Code:

select NAME 
  from MAIN 
inner
  join A as A1
    on MAIN.ID  = A1.ID 
   and A1.NUMBER = 'number1'
inner
  join A as A2
    on MAIN.ID  = A2.ID 
   and A2.NUMBER = 'number2'
...
group
    by NAME

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