< Boolean literal >s

A <Boolean literal> is one of these three words:

• TRUE
• FALSE
• UNKNOWN

Its <data type> is BOOLEAN. A <Boolean literal> of TRUE represents the truth value TRUE, a <Boolean literal> of FALSE represents the truth value FALSE and a <Boolean literal> of UNKNOWN represents the truth value UNKNOWN.

If you want to restrict your code to Core SQL, don't use <Boolean literal>s.