IF Statement

Syntax:

   IF condition THEN
      statements;
   [ELSIF condition THEN
      statements;]
   [ELSE
      statement;]
   END IF;

Note the spelling is ElsIF not ElseIF which you might expect from other languages.

'condition' may include logical comparisons...

true AND true = true
true OR true = true

false AND false = false
false OR false = false

null AND null = null
null OR null = null

true AND false = false
true OR false = true

true AND null = null
true OR null = true

false AND null = false
false OR null = null

NOT TRUE = FALSE
NOT FALSE = TRUE
NOT NULL = NULL