Relational Operators

All data types can be compared by using relational operators and the result is returned as a BOOLEAN value.

Relationship operators are binary operators. Two compared data types must be of the same type or they must support implicit conversion.

Table 1 lists the relational operators provided by DLI.

**Table 1** Relational operators
Operator	Result Type	Description
A = B	BOOLEAN	If A is equal to B, then TRUE is returned. Otherwise, FALSE is returned. This operator is used for value assignment.
A == B	BOOLEAN	If A is equal to B, then TRUE is returned. Otherwise, FALSE is returned. This operator cannot be used for value assignment.
A <=> B	BOOLEAN	If A is equal to B, then TRUE is returned. Otherwise, FALSE is returned. If A and B are NULL, then TRUE is returned. If A or B is NULL, then FALSE is returned.
A <> B	BOOLEAN	If A is not equal to B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned. This operator follows the standard SQL syntax.
A != B	BOOLEAN	This operator is the same as the <> logical operator. It follows the SQL Server syntax.
A < B	BOOLEAN	If A is less than B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A <= B	BOOLEAN	If A is less than or equal to B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A > B	BOOLEAN	If A is greater than B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A >= B	BOOLEAN	If A is greater than or equal to B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A BETWEEN B AND C	BOOLEAN	If A is greater than or equal to B and less than or equal to C, then TRUE is returned. Otherwise, FALSE is returned. If A, B, or C is NULL, then NULL is returned.
A NOT BETWEEN B AND C	BOOLEAN	If A is less than B or greater than C, TRUE is returned; otherwise, FALSE is returned. If A, B, or C is NULL, then NULL is returned.
A IS NULL	BOOLEAN	If A is NULL, then TRUE is returned. Otherwise, FALSE is returned.
A IS NOT NULL	BOOLEAN	If A is not NULL, then TRUE is returned. Otherwise, FALSE is returned.
A LIKE B	BOOLEAN	If A matches B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A NOT LIKE B	BOOLEAN	If A does not match B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A RLIKE B	BOOLEAN	This operator is used for the LIKE operation of JAVA. If A or its substring matches B, then TRUE is returned. Otherwise, FALSE is returned. If A or B is NULL, then NULL is returned.
A REGEXP B	BOOLEAN	The result is the same as A RLIKE B.