SQL查询错误＃1064

Question

So I have this query:

SELECT 
   t1.password 
FROM Session AS t1 
INNER JOIN Locations AS t2 ON 
    t2.id = t1.location_id AND 
    SQRT( POWER( CONVERT(t2.longitude,float(10)) - 132.456, 2) + 
        POWER( CONVERT(t2.latitude,float(10)) - 132.456, 2) ) < 100 
WHERE t1.end_distribution = 0 AND t1.end_session = 0

and I get this:

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'float(10)) - 132.456, 2) + POWER( CONVERT(t2.latitude,float(10)) - 132.456, 2) )' at line 13

Answer 1

Use

CONVERT(t2.longitude, float(10))

MySQL CONVERT SYNTAX

UPDATE

Depending on documentation above you can't convert expression to type float, use decimal instead.

CONVERT(t2.longitude, decimal(10))

Answer 2

You've got an invalid specification for the type on the CONVERT function. FLOAT(10) is not valid. It looks like your best alternative will be to use DECIMAL .

From the MySQL Reference Manual: http://dev.mysql.com/doc/refman/5.5/en/cast-functions.html

<snip>

The type for the result can be one of the following values:

BINARY[(N)]
CHAR[(N)]
DATE
DATETIME
DECIMAL[(M[,D])]
SIGNED [INTEGER]
TIME
UNSIGNED [INTEGER]

</snip>