Predicates
In our simplified BNF, predicate can be defined as a statement that can be evaluated to either TRUE or FALSE. Table H-2 "decodes" SQL syntax for predicates.Element | Syntax |
---|---|
<predicate> | <boolean_term> [{AND | OR} <boolean_term>,...] |
<boolean_term> | [NOT] <search_test> |
<search_test> | <comparison_test> | <between_test> | <in_test> | <like_test> | <null_test> | <exists_test> | <quantified_comparisson_test> |
<comparison_test> | <column_value> {= | <> | != | < | > | <= | >=} {<expression> | <single_row_subquery>} |
<between_test> | <column_value> [NOT] BETWEEN <expression> AND <expression> |
<in_test> | <column_value> [NOT] IN <expression_list> | <table_subquery> |
<like_test> | <column_value> [NOT] LIKE <pattern> [ESCAPE <value>] |
<null_test> | <column_value> IS [NOT] NULL |
<exists_test> | EXISTS <table_subquery> |
<quantified_ comparisson_test> | <column_value> {= | <> | != | < | > | <= | >=} {ALL | SOME | ANY} <table_subquery> |
<expression_list> | (<expression>,...) |
<expression> | <sub-expression> {+ | - | * | /} <sub-expression> |
<sub-expression> | [- | +] {<value> | <function>} |
<value> | <literal> | <variable> |
<column_value> | [qualifier.]<column_name> |