Floor of decimal as Parameter value in MySQL Prepared Statement throws error-CodePudding

My Goal:
Select middle row(s) of a table.

What have I tried?
I followed the approach mentioned in https://stackoverflow.com/a/33168093/282155.
Here's my code:

SELECT @a:=FLOOR((COUNT(*)-1)/2) FROM <Table> ORDER BY <Column>;  
PREPARE STMT FROM 'SELECT * FROM <Table> LIMIT ?, 1';  
EXECUTE STMT USING @a;

But my execute statement throws error:

ERROR 1210 (HY000) at line <line no>: Incorrect arguments to EXECUTE

My observations:

Floor of integer works fine when used in the prepared statement. e.g. FLOOR(COUNT(*)-1)
Execution of floor of decimal also works fine when used in Select statement: SELECT FLOOR((COUNT(*)-1)/2) FROM <Table>;

I am confused why my code is not working.

Thanks in advance.

CodePudding user response：

Consider using the following equivalent (yet valid) option.

SELECT @sql := CONCAT('SELECT * 
                       FROM <Table>
                       ORDER BY <Column>
                       LIMIT ', FLOOR((COUNT(*)-1)/2), ', 1') FROM <Table>;

PREPARE stmt FROM @sql;

EXECUTE stmt;

DEALLOCATE PREPARE stmt;

And don't forget to deallocate your statement preparation.

Check the demo here.