mysql - How can I select the distinct value of two tables? -

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i'm not sure it's possible select distinct value of 2 tables columns.

consider table1 like:

╔══════╗ ║ col1 ║ ╠══════╣ ║ aaa  ║ ║ aaa  ║ ║ bbb  ║ ║ bbb  ║ ╚══════╝

and table2 like:

╔══════╗ ║ col1 ║ ╠══════╣ ║ aaa  ║ ║ bbb  ║ ║ ccc  ║ ║ ccc  ║ ╚══════╝

the output be:

aaa bbb ccc

obviously like:

select distinct table1.col1 , table2.col1 table1 , table2;

won't work.

sqlfiddle

a simple union tricks

select col1 table1  union  select col1 table2;

there no need use distinct keyword union handle duplicates.

fyi if use union all duplicates won't handled anymore, need use distinct.


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