sql query on line

Question

I have one SQL table There are entries

+-----------------+------+
| idanother_table | Col1 |
+-----------------+------+
|              11 |   50 |
|              11 |   61 |
|              11 |   62 |
|              12 |   61 |
|              12 |   62 |
|              13 |   50 |
|              13 |   65 |
+-----------------+------+

I want a query that gives this result

+-----------------+------+
| idanother_table | Col1 |
+-----------------+------+
|              11 |   50 |
|              11 |   61 |
|              11 |   62 |
|              13 |   50 |
|              13 |   65 |
+-----------------+------+

So get all lines related to id_anothertable and col1 = 50.

So when for an id we have col1=50, we take all lines related to that id

Maybe this problem is a duplicate of another, but really i don't know how to name my problem so i have any base for research

Answer 1

You can try to use IN

SELECT * FROM t 
WHERE idanother_table IN 
(
    SELECT idanother_table 
    FROM t
    where Col1 = 50
)

or exists

SELECT * 
FROM t t1 
WHERE exists
(
    SELECT 1 
    FROM t tt
    where tt.Col1 = 50 and t1.idanother_table = tt.idanother_table
)