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Oracle® OLAP DML Reference
10g Release 1 (10.1)

Part Number B10339-02
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3.3 Dimensionality of OLAP DML Expressions

An expression is dimensioned by a union of the dimensions of all of the variables, dimensions, relations, formulas, qualified data references, and functions in the expression:

3.3.1 Determining the Dimensions of an Expression

You can find out the dimensions of an expression with the PARSE command and the INFO function. PARSE evaluates the text of an expression; the INFO indicates how the expression is interpreted.

This example illustrates the use of the DIMENSION keyword with the INFO function to retrieve the dimensions of the expression just analyzed by the PARSE command. Assume that you issue the following statement.

PARSE 'TOTAL(sales region)'

The statement produces the following output.


3.3.2 How Dimension Status Affects the Results of Expressions

The number of values an expression yields depends on the dimensions of the expression and the status of those dimensions. An expression yields one data value for each combination of dimension values in the current status. For example, when three dimension values are in status for month, and two for product, then the expression price gt 100 results in six values (3 times 2).

Thus, to get the desired results, you must ensure that the dimensions of an expression are limited to the range of data you want to consider. In addition, you must consider any PERMIT statements that might limit access to the dimensions of the data.

When you want to specify a single value without changing the current status you can use a qualified data reference (QDR). Using a QDR, you can qualify a dimension (which enables you to specify one dimension value in an expression) or one or more dimensions of a variable or relation. For more information on dimension status, see "Working with Subsets of Data"; for more information on QDRs, see "Specifying a Single Data Value in an Expression".

3.3.3 Changing the Dimensionality of an Expression

You can change the dimensionality of an expression or subexpression using the CHGDIMS function.