Oracle® OLAP DML Reference 10g Release 1 (10.1) Part Number B10339-02 |
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The LARGEST function returns the largest value of an expression. You can use this function to compare numeric values or date values.
Return Value
The data type of the expression. It can be INTEGER, LONGINT, DECIMAL, or DATE.
Syntax
LARGEST(expression [[STATUS] dimensions])
Arguments
The expression whose largest value is to be returned.
Can be specified when one or more of the dimensions of the result of the function are not dimensions of the expression. (See the description of the dimensions argument.) When you specify the STATUS keyword when this is not the case, Oracle OLAP produces an error.
In cases where one or more of the dimensions of the result of the function are not dimensions of the expression, the STATUS keyword might be required in order for Oracle OLAP to process the function successfully, or the STATUS keyword might provide a performance enhancement. See "The STATUS Keyword".
The dimensions of the result. By default, LARGEST returns a single value. When you indicate one or more dimensions for the results, LARGEST calculates the largest value along the dimensions that are specified and returns an array of values. Each dimension must be either a dimension of 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.
Notes
LARGEST is affected by the NASKIP option. When NASKIP is set to YES
(the default), LARGEST ignores NA
values and returns the largest value or values that are not NA
. When NASKIP is set to NO
, LARGEST returns NA
when any value of the expression is NA
. When all the values of the expression are NA
, LARGEST returns NA
for either setting of NASKIP.
When expression is dimensioned by a 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. 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 to the LARGEST function.
For each time period in the related dimension, Oracle OLAP finds the largest data value in any source time period that ends in the target time period. This method is used regardless of which dimension has the more aggregate periods.
When one or more of the dimensions of the result of the function are not dimensions of the expression, Oracle OLAP creates a temporary variable to use while processing the function. When you specify the STATUS keyword, Oracle OLAP uses the current status instead of the default status of the related dimensions for calculating the size of this temporary variable.
When the size of the temporary variable for the results of the function would exceed 2 gigabytes, you must specify the STATUS keyword in order for Oracle OLAP to execute the function successfully. When the dimensions of the expression are limited to a few values and are physically fragmented, you can specify the STATUS keyword to improve the performance of the function.
When you use the LARGEST function with the STATUS keyword for an expression that requires going outside of the status for results (for example, with the LEAD or LAG functions or with a qualified data reference), the results outside of the status will be returned as NA
.
Examples
Example 15-33 Finding the Largest Monthly Sales
This example uses the LARGEST function to find the largest monthly sportswear sales for each district during the first half of 1996. To see the largest sales figure for each district, specify district
as the dimension of the results.
LIMIT product TO 'Sportswear' LIMIT month TO 'Jan96' TO 'Jun96' REPORT HEADING 'Largest Sales' LARGEST(sales district)
The preceding statements produce the following output.
Largest DISTRICT Sales -------------- ---------- Boston 79,630.20 Atlanta 177,967.49 Chicago 112,792.78 Dallas 175,716.31 Denver 97,236.88 Seattle 60,322.88