Mysql function returning a value from a query

Question

i want to create a function which calculates a value using a query and I am having a problem returning the value:

Shortened, my query is:

CREATE FUNCTION func01(value1 INT , monto DECIMAL (10,2)) RETURNS DECIMAL(10,2) BEGIN SET @var_name = 0; select @var_name=if(value1 = 1,monto * table.divisa_dolar,table.monto *divisa_euro) from table where data_init = 1; return @var_nam; END 

I get a SQL syntax error.

SQL Error (1064): You have an error in your SQL syntax;

Answer 1

Assuming these are all generic names (table will not be a good table name), the problem is you can't use == for comparison. You are also missing some key syntax (DECLARE, SELECT INTO, etc.).

Change to this:

CREATE FUNCTION func01(value1 INT , monto DECIMAL (10,2)) RETURNS DECIMAL(10,2) DETERMINISTIC BEGIN   DECLARE var_name DECIMAL(10,2);   SET var_name = 0;   SELECT if(value1 = 1,monto *divisa_dolar,monto *divisa_euro) INTO var_name     FROM table     WHERE data_init = 1;   RETURN var_name; END 

MySQL Comparison Functions and Operators

Related Question: Single Equals in MYSQL

Function Help: http://www.databasejournal.com/features/mysql/article.php/3569846/MySQL-Stored-Functions.htm