. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 4.1. Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.3. Conditional Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 4.1.4. NULL in Expressions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311 6.1.16. Common Table Expressions (“WITH … AS … SELECT”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312 6.2. INSERT

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 4.1. Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.3. Conditional Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 4.1.4. NULL in Expressions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 6.1.14. Common Table Expressions (“WITH … AS … SELECT”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 6.2. INSERT

...............................................................................31 4.2. Value Expressions............................................................................................... ..........................................................................35 4.2.7. Aggregate Expressions........................................................................................35 4.2.8 ................................................................................75 7.2. Table Expressions...............................................................................................

...............................................................................30 4.2. Value Expressions............................................................................................... ..........................................................................34 4.2.7. Aggregate Expressions........................................................................................34 4.2.8 ................................................................................66 7.2. Table Expressions...............................................................................................

...............................................................................30 4.2. Value Expressions............................................................................................... ..........................................................................34 4.2.7. Aggregate Expressions........................................................................................35 4.2.8 ................................................................................73 7.2. Table Expressions...............................................................................................

...............................................................................29 4.2. Value Expressions............................................................................................... ..........................................................................32 4.2.7. Aggregate Expressions.................................................................................33 4.2.8. Type ................................................................................63 7.2. Table Expressions...............................................................................................

...............................................................................31 4.2. Value Expressions............................................................................................... ..........................................................................35 4.2.7. Aggregate Expressions........................................................................................35 4.2.8 ................................................................................75 7.2. Table Expressions...............................................................................................

behaviour of NULL in Firebird SQL, points out common pitfalls and shows you how to deal safely with expressions that contain NULL or may resolve to NULL. If you only need a quick reference to refresh your memory (Firebird 2+) In Firebird 2 and higher only, you can test for the null-encompassing equality of two expressions with “IS [NOT] DISTINCT FROM”: if ( A is distinct from B ) then... Chapter 2. NULL support in Firebird SQL 7 if ( Buyer1 is not distinct from Buyer2 ) then... Fields, variables and other expressions are considered: • DISTINCT if they have different values or if one of them is NULL and the other

...............................................................................30 4.2. Value Expressions............................................................................................... ..........................................................................34 4.2.7. Aggregate Expressions........................................................................................35 4.2.8 ................................................................................73 7.2. Table Expressions...............................................................................................

...............................................................................35 4.2. Value Expressions............................................................................................... ..........................................................................39 4.2.7. Aggregate Expressions........................................................................................40 4.2.8 ................................................................................83 7.2. Table Expressions...............................................................................................