Boolean (Logical) Values

   

PostgreSQL supports a single Boolean (or logical) data type: BOOLEAN ( BOOLEAN can be abbreviated as BOOL ).

Size and Valid Values

A BOOLEAN can hold the values TRUE , FALSE , or NULL , and consumes a single byte of storage.

Syntax for Literal Values

Table 2.16 shows the alternate spellings for BOOLEAN literals.

Table 2.16. BOOLEAN Literal Syntax

Common Name

Synonyms

TRUE

true , 't' , 'y' , 'yes' , 1

FALSE

false, 'f', 'n', 'no', 0

Supported Operators

The only operators supported for the BOOLEAN data type are the logical operators shown in Table 2.17:

Table 2.17. Logical Operators for BOOLEAN

Data Types

Valid Operators ( q )

BOOLEAN q BOOLEAN

AND OR NOT

I covered the AND , OR , and NOT operators in Chapter 1. For a complete definition of these operators, see Tables 1.3, 1.4, and 1.5.

   


PostgreSQL
PostgreSQL (2nd Edition)
ISBN: 0672327562
EAN: 2147483647
Year: 2005
Pages: 220
Authors: Korry Douglas

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