what is the meaning of the operator *=? [duplicate]

This question already has answers here: 开发者_如何学C Closed 11 years ago.

Possible Duplicate:

SQL: What does =* mean?

Hi all

I got a design someone made and he stated the following on one of the SQLs:

Select * from table_A, table_B Where table_A.ID *= table_B.ID

Can anyone tell what does '*=' operator stands for?

Thanks.

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That is equivalent to a left join in mySql. It's just on older (weirder) syntax.

It's the same as this:

SELECT * FROM table_A
LEFT JOIN table_B
ON table_A.ID = table_B.ID