SQL - Predicate

About

Predicate is an expression that evaluates to TRUE, FALSE, or UNKNOWN.

You have two principal types of predicates:

join predicates
or filter predicates

Predicates are used in:

WHERE clauses,
HAVING clauses,
JOIN conditions,
FROM clauses,

and other constructs where a Boolean value is required.

Articles Related

Example of Predicates Operator

BETWEEN
EXISTS
IN
IS [NOT] NULL
LIKE

Example of predicates information

The output of an Oracle explain plain contains a predicate information section. You can see for instance the the filter clause but also the join clause.

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - access("I1"."N"="MAP"."I2")
   3 - filter("I1"."V"='cx')
   5 - filter("I2"."V"='y')
   6 - access("I2"."N"="MAP"."I2")