Using a SELECT Statement in a LET Statement

The examples in this section use a SELECT statement in a LET statement. You can use a SELECT statement to assign values to one or more variables on the left side of the equals ( = ) operator, as the following example shows:

LET a,b = (SELECT c1,c2 FROM t WHERE id = 1);
LET a,b,c = (SELECT c1,c2 FROM t WHERE id = 1), 15;

You cannot use a SELECT statement to make multiple values operate on other values. The following example is invalid:

LET a,b = (SELECT c1,c2 FROM t) + (10,15); -- INVALID CODE

Because a LET statement is equivalent to a SELECT ... INTO statement, the two statements in the following example have the same results: a=c and b=d:

CREATE PROCEDURE proof()
   DEFINE a, b, c, d INT;
   LET a,b = (SELECT c1,c2 FROM t WHERE id = 1);
   SELECT c1, c2 INTO c, d FROM t WHERE id = 1
END PROCEDURE 

If the SELECT statement returns more than one row, you must enclose the SELECT statement in a FOREACH loop.

For a description of SELECT syntax and usage, see SELECT.