SELECT-FROM inside an IF STATEMENT

Question

It is not very clear to me if I can use a select-from statement as a condition for an IF STATEMENT For example

IF(SELECT quantity
  FROM warehouse)>(SELECT quantity
                  FROM warehouse2) then ecc

Can I do something like that?

No, you can't. There is no `if (implicit cursor) then...` syntax in PL/SQL. — William Robertson, May 21 '20 at 21:29

score 4 · Accepted Answer · answered May 18 '20 at 15:52

4

I think you should using the variable for them.

DECLARE 
    V_quantity_WH1 NUMBER;
    V_quantity_WH2 NUMBER;
BEGIN
    --Sum qty 1 --------------
    SELECT SUM(quantity) INTO V_quantity_WH1 FROM warehouse;

    --Sum qty 2 --------------
    SELECT SUM(quantity) INTO V_quantity_WH2 FROM warehouse2;

    --Compare qty1 and qty2 ----------------
    IF (V_quantity_WH1 > V_quantity_WH2) THEN
        ......;
    END IF; 
END;

answered May 18 '20 at 15:52

Hung Le

141
9

Agree. This is clearer for people to parse. Inlining a select statement makes little or no sense to me. I can't see how it would benefit anyone. – Dom G May 18 '20 at 16:52

score 0 · Answer 2 · answered May 18 '20 at 16:54

0

It is impossible. The select ... expression is a pointer, IF expects a boolean expression: IF *boolean_expression* THEN *statement* END IF;

answered May 18 '20 at 16:54

vnskv

61
5

SELECT-FROM inside an IF STATEMENT

2 Answers2