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4

# SQL Conditions

This chapter presents the syntax for combining one or more expressions and logical (Boolean) operators to specify a condition.

This chapter includes the following section:

Syntax for SQL Condition Types

## Syntax for SQL Condition Types

A condition speciﬁes a combination of one or more expressions and logical (Boolean) operators and returns a value of TRUE, FALSE, or unknown.

Conditions have several forms. Table 4–1 shows the syntax for each form of condition. Refer to Chapter 5, "Subclauses" for the syntax of the subclauses found in the following table.

Table 4–1 Syntax for SQL Condition Types

 SQL Condition Type Syntax Compound conditions { (condition) | NOT condition | condition { AND | OR } condition } EQUALS_PATH condition EQUALS_PATH (column, path_string [, correlation_integer ]) EXISTS condition EXISTS (subquery)

SQL Conditions 4-1

Syntax for SQL Condition Types

Table 4–1 (Cont.) Syntax for SQL Condition Types

 SQL Condition Type Syntax Floating-point conditions expr IS [ NOT ] { NAN | INFINITE } Group comparison { expr condition { = | != | ^= | <> | > | < | >= | <= } { ANY | SOME | ALL } ({ expression_list | subquery })

| expr [, expr ]...

{ = | != | ^= | <> }

{ ANY | SOME | ALL }

({ expression_list [, expression_list ]...

 | subquery } ) } where !=, ^=, and <> test for inequality IN conditions { expr [ NOT ] IN ({ expression_list | subquery }) | ( expr [, expr ]... [ NOT ] IN ({ expression_list [, expression_list ]... | subquery } ) ) } IS A SET conditions nested_table IS [ NOT ] A SET IS ANY condition [ dimension_column IS ] ANY IS EMPTY conditions nested_table IS [ NOT ] EMPTY IS OF TYPE conditions expr IS [ NOT ] OF [ TYPE ] ([ ONLY ] [ schema. ] type [, [ ONLY ] [ schema. ] type ]... ) IS PRESENT condition cell_reference IS PRESENT LIKE condition char1 [ NOT ] ( LIKE | LIKEC | LIKE2 | LIKE4 ) char2 [ ESCAPE esc_char ] Logical conditions { NOT | AND | OR } MEMBER condition expr [ NOT ] MEMBER [ OF ] nested_table NULL conditions expr IS [ NOT ] NULL

4-2 Oracle Database SQL Quick Reference

Syntax for SQL Condition Types

Table 4–1 (Cont.) Syntax for SQL Condition Types

 SQL Condition Type Syntax Range conditions expr [ NOT ] BETWEEN expr AND expr REGEXP_LIKE condition REGEXP_LIKE(source_string, pattern [, match_parameter ] ) Simple comparison { expr condition { = | != | ^= | <> | > | < | >= | <= } expr | (expr [, expr ]...) { = | != | ^= | <> } (subquery) } where !=, ^=, and <> test for inequality SUBMULTISET conditions nested_table1 [ NOT ] SUBMULTISET [ OF ] nested_table2 UNDER_PATH condition UNDER_PATH (column [, levels ], path_string [, correlation_integer ] )

SQL Conditions 4-3

Syntax for SQL Condition Types

4-4 Oracle Database SQL Quick Reference

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