Running Aggregate Functions
Running aggregate functions are similar to functional aggregates in that they take a set of records as input, but instead of outputting the single aggregate for the entire set of records, they output the aggregate based on records encountered so far. This section describes the running aggregate functions supported by the Oracle BI Server. MavgCalculates a moving average (mean) for the last n rows of data in the result set, inclusive of the current row. Syntax: MAVG (n_expression, n) where:
n_expression | Any expression that evaluates to a numerical value. | n | Any positive integer. Represents the average of the last n rows of data. |
The average for the first row is equal to the numeric expression for the first row. The average for the second row is calculated by taking the average of the first two rows of data. The average for the third row is calculated by taking the average of the first three rows of data, and so on until you reach the nth row, where the average is calculated based on the last n rows of data. MSUMThis function calculates a moving sum for the last n rows of data, inclusive of the current row. The sum for the first row is equal to the numeric expression for the first row. The sum for the second row is calculated by taking the sum of the first two rows of data. The sum for the third row is calculated by taking the sum of the first three rows of data, and so on. When the nth row is reached, the sum is calculated based on the last n rows of data. Syntax: MSUM (n_expression, n) Where:
n_expression | Any expression that evaluates to a numerical value. | n | Any positive integer. Represents the sum of the last n rows of data. |
Example: The following example shows a query that uses the MSUM function and the query results. select month, revenue, MSUM(revenue, 3) as 3_MO_SUM from sales_subject_area MONTH | REVENUE | 3_MO_SUM | JAN | 100.00 | 100.00 | FEB | 200.00 | 300.00 | MAR | 100.00 | 400.00 | APRIL | 100.00 | 400.00 | MAY | 300.00 | 500.00 | JUNE | 400.00 | 800.00 | JULY | 500.00 | 1200.00 | AUG | 500.00 | 1400.00 | SEPT | 500.00 | 1500.00 | OCT | 300.00 | 1300.00 | NOV | 200.00 | 1000.00 | DEC | 100.00 | 600.00 |
RSUMThis function calculates a running sum based on records encountered so far. The sum for the first row is equal to the numeric expression for the first row. The sum for the second row is calculated by taking the sum of the first two rows of data. The sum for the third row is calculated by taking the sum of the first three rows of data, and so on. Syntax: RSUM (n_expression) Where:
n_expression | Any expression that evaluates to a numerical value. |
Example: The following example shows a query that uses the RSUM function and the query results. select month, revenue, RSUM(revenue) as RUNNING_SUM from sales_subject_area MONTH | REVENUE | RUNNING_SUM | JAN | 100.00 | 100.00 | FEB | 200.00 | 300.00 | MAR | 100.00 | 400.00 | APRIL | 100.00 | 500.00 | MAY | 300.00 | 800.00 | JUNE | 400.00 | 1200.00 | JULY | 500.00 | 1700.00 | AUG | 500.00 | 2200.00 | SEPT | 500.00 | 2700.00 | OCT | 300.00 | 3000.00 | NOV | 200.00 | 3200.00 | DEC | 100.00 | 3300.00 |
RCOUNTThis function takes a set of records as input and counts the number of records encountered so far. Syntax: RCOUNT (Expr) Where:
Expr | An expression of any data type. |
Example: The following example shows a query that uses the RCOUNT function and the query results. select month, profit, RCOUNT(profit) from sales_subject_area where profit > 200. MONTH | PROFIT | RCOUNT (profit | MAY | 300.00 | 2 | JUNE | 400.00 | 3 | JULY | 500.00 | 4 | AUG | 500.00 | 5 | SEPT | 500.00 | 6 | OCT | 300.00 | 7 |
RMAXThis function takes a set of records as input and shows the maximum value based on records encountered so far. The specified data type must be one that can be ordered. Syntax: RMAX (expression) Where:
expression | An expression of any data type. The data type must be one that has an associated sort order. |
Example: The following example shows a query that uses the RMAX function and the query results. select month, profit, RMAX(profit) from sales_subject_area MONTH | PROFIT | RMAX (profit) | JAN | 100.00 | 100.00 | FEB | 200.00 | 200.00 | MAR | 100.00 | 200.00 | APRIL | 100.00 | 200.00 | MAY | 300.00 | 300.00 | JUNE | 400.00 | 400.00 | JULY | 500.00 | 500.00 | AUG | 500.00 | 500.00 | SEPT | 500.00 | 500.00 | OCT | 300.00 | 500.00 | NOV | 200.00 | 500.00 | DEC | 100.00 | 500.00 |
RMINThis function takes a set of records as input and shows the minimum value based on records encountered so far. The specified data type must be one that can be ordered. Syntax: RMIN (expression) Where:
expression | An expression of any data type. The data type must be one that has an associated sort order. |
Example: The following example shows a query that uses the RMIN function and the query results. select month, profit, RMIN(profit) from sales_subject_area MONTH | PROFIT | RMIN (profit) | JAN | 400.00 | 400.00 | FEB | 200.00 | 200.00 | MAR | 100.00 | 100.00 | APRIL | 100.00 | 100.00 | MAY | 300.00 | 100.00 | JUNE | 400.00 | 100.00 | JULY | 500.00 | 100.00 | AUG | 500.00 | 100.00 | SEPT | 500.00 | 100.00 | OCT | 300.00 | 100.00 | NOV | 200.00 | 100.00 | DEC | 100.00 | 100.00 |
| 
|Archiver|小黑屋|手机版|壹佰网 ERP100
( 京ICP备19053597号-2 )
IP卡
狗仔卡
发表于 2012/10/21 10:35:17
该贴已经同步到 
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
抢沙发
千斤顶
显身卡
发表于 2012/10/21 14:43:28
楼主