sql query to return all rows with same column value

Question

I have a DB like

    column_1 | column_2 | column_3
    ------------------------------
         aaa | bbb      | ccc
         xys | hkj      | fgh
         dfs | jhv      | ccc
         cfg | rty      | fgh
         iyd | olp      | ccc
         gdv | tdr      | www

I want to get the result such that all the rows that have the same value in column_3 are printed out along with their column_3 value

        column_1 | column_3
        --------------------
             aaa | ccc
             dfs | ccc
             iyd | ccc
             cfg | fgh
             xys | fgh
             gdv | www

I know SELECT DISTINCT column_3 FROM table_name; gives me all the unique names of column_3 but how do I get all the column_1 values that depend on column_3 ?

Answer 1

Is it possible you're overthinking this? I believe you want

 SELECT column_1,
        column_3
   FROM table_name
  ORDER BY column_3, column_1

Answer 2

Select ...
From table_name As T
Where Exists    (
                Select 1
                From table_name As T2
                Where T2.column_3 = T.column_3
                    And T2.<Primary Key Column> <> T.<Primary Key Column>
                )

Obviously, you would replace <Primary Key Column> with the column(s) that uniquely identify each row in table_name . If column_1 is that column, then we would get:

Select ...
From table_name As T
Where Exists    (
                Select 1
                From table_name As T2
                Where T2.column_3 = T.column_3
                    And T2.column_1 <> T.column_1
                )

Answer 3

I haven't tried this in MYSQL yet, but in SQL Server this work.

CREATE TABLE table_name (column_1 CHAR(3), column_2 CHAR(3), column_3 CHAR(3))
INSERT INTO table_name VALUES 
('aaa','bbb','ccc')
,('xys','hkj','fgh')
,('dfs','jhv','ccc')
,('cfg','rty','fgh')
,('iyd','olp','ccc')
,('gdv','tdr','www')

SELECT column_1  
     , column_3 
  FROM table_name a
 WHERE EXISTS(SELECT column_3 
               FROM table_name b
              GROUP BY column_3
             HAVING COUNT(column_3) > 0
                AND b.column_3 = a.column_3)