Firebird Null Guide NULL behaviour and pitfalls in Firebird SQL Paul Vinkenoog Version 1.2, 30 June 2020 Table of Contents 1. What is NULL? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. NULL as a default state. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. NULL support in Firebird 1. Disallowing NULL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.2. Testing for NULL . . . . . . .

Guide Firebird et NULL Comportement et précautions au sujet de NULL dans Firebird SQL Paul Vinkenoog Traduction en français: Philippe Makowski 04 mai 2005 - Document version 0.2.1-fr 2 Table des matières ............ 3 Qu'est ce que NULL? .............................................................................................................................. 3 NULL dans les expressions ......... .............. 3 Expressions retournant NULL .......................................................................................................... 4 NULL dans des expressions booléennes ........

Guía de NULL en Firebird Comportamiento y dificultades de NULL en Firebird Paul Vinkenoog 22 de julio de 2005 - Versión de documento 0.2-es-2 Traducción al castellano: Víctor Zaragoza 2 Tabla de ............... 3 ¿Qué es NULL? ...................................................................................................................................... 3 NULL en expresiones ........... ............... 3 Expresiones que devuelven NULL ................................................................................................... 4 NULL en expresiones booleanas ..................

NULL в СУБД Firebird Подводные камни и поведение NULL в СУБД Firebird Paul Vinkenoog 19 октября 2006 – Версия документа 0.2-ru Перевод документа на русский язык: Сергей Ковалёв 2 Содержание Введение ............... 3 Что такое NULL? ................................................................................................................................... 3 NULL в выражениях .............. .................. 3 Выражения, возвращающие NULL ................................................................................................ 4 NULL в логических выражениях .....................

....................................................................................50 5.3.2. Not-Null Constraints....................................................................................52 Mapping................................................................................1093 43.3.2. Null, None............................................................................................ Configuration.............................................................................2785 F.25.6.2. NULL Handling ........................................................................2786 F.25.6.3. Security

....................................................................................55 5.3.2. Not-Null Constraints...................................................................................... .....................................................................................1161 43.3.2. Null, None............................................................................................ ...................................................................................2955 F.25.6.2. NULL Handling ...............................................................................2956 F.25

....................................................................................50 5.3.2. Not-Null Constraints....................................................................................52 Mapping................................................................................1059 42.3.2. Null, None............................................................................................ Configuration.............................................................................2627 F.25.6.2. NULL Handling ........................................................................2627 F.25.6.3. Security

....................................................................................55 5.3.2. Not-Null Constraints...................................................................................... .....................................................................................1126 42.3.2. Null, None............................................................................................ ...................................................................................2794 F.25.6.2. NULL Handling ...............................................................................2794 F.25

of the left table. When outputting a left-table row for which there is no right-table match, empty (null) values are substituted for the right-table columns. Exercise: There are also right outer joins real, elevation int -- (in ft) ); CREATE TABLE capitals ( state char(2) UNIQUE NOT NULL ) INHERITS (cities); In this case, a row of capitals inherits all columns (name, population, and ................................................................................... 65 5.3.2. Not-Null Constraints ................................................................................. 68 5

of the left table. When outputting a left-table row for which there is no right-table match, empty (null) values are substituted for the right-table columns. 12 The SQL Language Exercise: There are real, elevation int -- (in ft) ); CREATE TABLE capitals ( state char(2) UNIQUE NOT NULL ) INHERITS (cities); In this case, a row of capitals inherits all columns (name, population, and Constraints ............................................................................... 61 5.3.2. Not-Null Constraints ............................................................................ 63 5.3.3