A predicate is specified in a WHERE condition in a statement which is "true", "false", or "unknown". The result is generated by applying the predicate to a specific row in a result table or to a group of rows in a table that was formed by the GROUP condition.


<predicate> ::=
| <bool_predicate>
| <comparison_predicate>
| <default_predicate>
| <exists_predicate>
| <in_predicate>
| <join_predicate>
| <like_predicate>
| <null_predicate>
| <quantified_predicate>
| <rowno_predicate>
| <sounds_predicate>


SQL Tutorial, Conditions: Comparison, AND, OR, BETWEEN, IN, Negative Conditions: NOT, Searching for Character Strings: LIKE, Joins: Information from Several Tables


·        Columns in a table with the same code attribute can be compared.

·        Columns that have different code attributes such as ASCII and UNICODE can be compared.

·        Columns with the code attribute ASCII or UNICODE can be compared with date values, time values- or time stamp values.

·        LONG columns can only be used in the NULL predicate.