COUNT |
The COUNT function counts the number of TRUE values of a Boolean expression. It returns 0 (zero) when no values of the expression are TRUE.
Return Value
INTEGER
Syntax
COUNT(boolean-expression [dimensions])
Arguments
The Boolean expression whose TRUE values are to be counted.
The dimensions of the result. By default, COUNT returns a single count of all TRUE values. When you indicate one or more dimensions for the results, COUNT counts TRUE values along the dimensions that are specified and returns an array of values. Each dimension must be either a dimension of boolean-expression or related to one of its dimensions. When it is a related dimension, you can specify the name of the relation instead of the dimension name. This enables you to choose which relation is used when there is more than one.
When boolean-expression is dimensioned by dimension of type DAY, WEEK, MONTH, QUARTER, or YEAR, you can specify any other DAY, WEEK, MONTH, QUARTER, or YEAR dimension as a related dimension. Oracle OLAP uses the implicit relation between the dimensions. For each time period in the related dimension, Oracle OLAP tests the data values for all the source time periods that end in the target time period. This method is used regardless of which dimension has the more aggregate time periods. To control the mapping of one DAY, WEEK, MONTH, QUARTER, or YEAR dimension to another (for example, from weeks to months), you can define an explicit relation between the two dimensions and specify the name of the relation as the dimension argument.
Notes
The Effect of NASKIP on COUNT
COUNT is affected by the NASKIP option. When NASKIP is set to YES (the default), COUNT returns the number of TRUE values of the Boolean expression, regardless of how many other values are NA. When NASKIP is set to NO, COUNT returns NA when any value of the expression is NA. When all the values of the expression are NA, COUNT returns NA for either setting of NASKIP.
Examples
Counting True Values by District
You can use COUNT to find the number of months in which each district sold more than 2,000 units of sportswear. To obtain a count for each district, specify district as the dimension for the result.
LIMIT product TO 'SPORTSWEAR' REPORT HEADING 'Count' COUNT(units GT 2000, district)
The preceding statement statements produce the following output.
DISTRICT Count -------------- ---------- Boston 0 Atlanta 23 Chicago 11 Dallas 24 Denver 7 Seattle 0