Skip Headers
Oracle® Database SQL Language Quick Reference
11g Release 2 (11.2)

Part Number E17119-06
Go to Documentation Home
Home
Go to Book List
Book List
Go to Table of Contents
Contents
Go to Index
Index
Go to Master Index
Master Index
Go to Feedback page
Contact Us

Go to previous page
Previous
Go to next page
Next
PDF · Mobi · ePub

Syntax for SQL Expression Types

An expression is a combination of one or more values, operators, and SQL functions that evaluate to a value. An expression generally assumes the data type of its components.

Expressions have several forms. The sections that follow show the syntax for each form of expression. Refer to Chapter 5, "Subclauses" for the syntax of the subclauses.

See Also:

Expressions in Oracle Database SQL Language Reference for detailed information about SQL expressions

CASE expressions

CASE { simple_case_expression
     | searched_case_expression
     }
     [ else_clause ]
     END

Column expressions

A column expression can be a simple expression, compound expression, function expression, or expression list, containing only columns of the subject table, constants, and deterministic functions.

Compound expressions

{ (expr)
| { + | - | PRIOR } expr
| expr { * | / | + | - | || } expr
}

Note: The double vertical bars are part of the syntax
      (indicating concatenation) rather than BNF notation.

CURSOR expressions

CURSOR (subquery)

Datetime expressions

expr AT
   { LOCAL
   | TIME ZONE { ' [ + | - ] hh:mm'
               | DBTIMEZONE
               | 'time_zone_name'
               | expr
               }
   }

Function expressions

You can use any built-in SQL function or user-defined function as an expression.

Interval expressions

( expr1 - expr2 )
   { DAY [ (leading_field_precision) ] TO
     SECOND [ (fractional_second_precision) ]
   | YEAR [ (leading_field_precision) ] TO
     MONTH
   }

Model expressions

{ measure_column [ { condition | expr }[ , { condition | expr } ...] ]
| aggregate_function 
     { [ { condition | expr }[ , { condition | expr } ...] ]
     | [ single_column_for_loop [, single_column_for_loop] ... ]
     | [ multi_column_for_loop ]
     }
| analytic_function
}

Note:

The outside square brackets shown in boldface type are part of the syntax. In this case, they do not represent optionality.

Object access expressions

{ table_alias.column.
| object_table_alias.
| (expr).
}
{ attribute [.attribute ]...
  [.method ([ argument [, argument ]... ]) ]
| method ([ argument [, argument ]... ])
}

Placeholder expressions

:host_variable
   [ [ INDICATOR ]
     :indicator_variable
   ]

Scalar subquery expressions

A scalar subquery expression is a subquery that returns exactly one column value from one row.

Simple expressions

{ [ query_name.
  | [schema.]
    { table. | view. | materialized view. }
  ] { column | ROWID }
| ROWNUM
| string
| number
| sequence. { CURRVAL | NEXTVAL }
| NULL
}

Type constructor expressions

[ NEW ] [ schema. ]type_name
   ([ expr [, expr ]... ])