Re: SELECT 1 FROM DUAL

[Felix Geerinckx]

wanted wrote:
> Hi all,
> Can someone explain to me what is "SELECT 1 FROM
> DUAL"
> Is dual a built-in table in MYSQL?
>
> thanks.

Quote from http://dev.mysql.com/doc/refman/5.0/en/select.html:

"You are allowed to specify DUAL as a dummy table name in situations where no tables are referenced:

mysql> SELECT 1 + 1 FROM DUAL;
-> 2

DUAL is purely for compatibility with some other database servers that require a FROM clause. MySQL does not require the clause if no tables are referenced."

--
felix
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