Some trivia about SQL and booleans:
SQL 1992 defines three values for a boolean:
<truth value> ::= TRUE | FALSE | UNKNOWN
True booleans aren’t always supported, though. Here’s the truth table of boolean support:
SQL Dialect | Supports booleans |
---|---|
DB2 | 0 (use 1/0 instead) |
Derby | true (you can safely use true/false) |
H2 | true |
HSQLDB | true |
Ingres | true |
MySQL | true |
Oracle | 0 |
Postgres | true |
SQL Server | 0 |
SQLite | 0 |
Sybase ASE | 0 |
Sybase SQL Anywhere | 0 |
Trivia… but nice to know.