How to declare a variable in MySQL for a normal query?

mysql variables variable-declaration
EOB picture EOB · Jun 5, 2012 · Viewed 60.7k times · Source

How can I declare a variable for a normal query in MySQL?

e.g.,

declare @myVar date;
set @myVar = something;

select * from someTable where someColumn = @myVar;

I tried and the syntax seems to be wrong...what am I missing?

Answer

aleroot picture aleroot · Jun 5, 2012

You can declare a session variable in this way : 

SET @myvarname := 'value';

or a local variable in this way : 

DECLARE my_variable varchar(30)

also: 

DECLARE my_variable varchar(30) DEFAULT 'value'

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