Oracle® OLAP Reference 10g Release 2 (10.2) Part Number B14350-01 |
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OLAP_EXPRESSION_BOOL
acts as a boolean single-row function within the context of a SELECT FROM OLAP_TABLE
statement. You can specify OLAP_EXPRESSION_BOOL
in the same way you specify other Oracle single-row functions, notably in the select list and WHERE
clauses.
Single-row functions return a single result row for every row of a queried table or view. Oracle supports a number of predefined single-row functions, for example COS
, LOG
, and ROUND
which return numeric data, and UPPER
and LOWER
which return character data. For more information on single-row functions, refer to the Oracle Database SQL Reference.
The OLAP single-row functions, OLAP_EXPRESSION
and its variants for text, date, and boolean data, return the result of an OLAP DML expression that you specify. The OLAP DML supports a rich syntax for specifying computations ranging from simple arithmetic expressions to statistical, financial, and time-series operations.
You can use OLAP_EXPRESSION_BOOL
to dynamically perform any valid boolean expression within an analytic workspace and retrieve its results. For more information on boolean expressions in the OLAP DML, search for "boolean expression" in the Oracle OLAP DML Reference.
OLAP_TABLE
uses a limit map to present the multidimensional data from an analytic workspace in tabular form. The limit map specifies the columns of the logical table. When an OLAP_EXPRESSION_BOOL
function is specified in the select list of the query, OLAP_TABLE
generates an additional column for the results of the function.
To use OLAP_EXPRESSION_BOOL
, you must specify a ROW2CELL
clause in the limit map used by OLAP_TABLE
. ROW2CELL
identifies a RAW
column that OLAP_TABLE
populates with information used by the OLAP single-row functions.