Condition:
 
   .-Logical_Operator-----------------------------------.
   V                                      (1)           |
|----+-----+--+-| Comparison Conditions |-------------+-+-------|
     '-NOT-'  |                             (2)       |
              +-| Condition with Subquery |-----------+
              |  (3)                             (4)  |
              '--------| User-Defined Function |------'
 

1. See page Comparison Conditions (Boolean Expressions)
2. See page Condition with Subquery
3. Dynamic Server only
4. See page User-Defined Functions

A condition is a search criterion, optionally connected by the logical operators AND or OR. Conditions can be classified into the following categories:

• Comparison conditions (also called filters or Boolean expressions)
• Conditions within a subquery
• User-defined functions (Dynamic Server only)

A condition can contain an aggregate function only if it is used in the HAVING clause of a SELECT statement or in the HAVING clause of a subquery.

No aggregate function can appear in a condition in the WHERE clause of a DELETE, SELECT, or UPDATE statement unless both of the following are TRUE:

• Aggregate is on a correlated column originating from a parent query.
• The WHERE clause appears in a subquery within a HAVING clause.

In Dynamic Server, user-defined functions are not valid as conditions in the following contexts:

• In the HAVING clause of a SELECT statement
• In the definition of a check constraint

SPL routines are not valid as conditions in the following contexts:

• In the definition of a check constraint
• In the ON clause of a SELECT statement
• In the WHERE clause of a DELETE, SELECT, or UPDATE statement

External routines are not valid as conditions in the following contexts:

• In the definition of a check constraint
• In the ON clause of a SELECT statement
• In the WHERE clause of a DELETE, SELECT, or UPDATE statement
• In the WHEN clause of CREATE TRIGGER
• In the IF, CASE, or WHILE statements of SPL