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Extracts the value from a column that is a specified number of rows after the current value.
The row from which to extract a value is determined by the order in which the rows are organized at the time that the transform is executed. If you are working on a randomly generated sample of your dataset, the values that you see for this function might not correspond to the values that are generated on the full dataset during job execution.
 If the next value is missing or null, this function generates a missing value.
 You can use the
group
andorder
parameters to define the groups of records and the order of those records to which this transform is applied.  This function works with the following transforms:
Basic Usage
window value:NEXT(myNumber, 1) order:Date
Output: Generates the new column, which contains the value in the row in the myNumber
column immediately after the current row when the dataset is ordered by Date
.
Syntax
window value:NEXT(col_ref, k_integer) order: order_col [group: group_col]
Argument  Required?  Data Type  Description 

col_ref  Y  string  Name of column whose values are applied to the function 
k_integer  Y  integer (positive)  Number of rows after the current one from which to extract the value 
For more information on the order
and group
parameters, see Window Transform.
For more information on syntax standards, see Language Documentation Syntax Notes.
col_ref
Name of the column whose values are used to extract the value that is kinteger
values after the current one.
 Multiple columns and wildcards are not supported.
Usage Notes:
Required?  Data Type  Example Value 

Yes  String (column reference)  myColumn 
k_integer
Integer representing the number of rows after the current one from which to extract the value.
 Value must be a positive integer. For negative values, see PREV Function.

k=1
represents the immediately following row value.  If k is greater than or equal to the number of values in the column, all values in the generated column are missing. If a
group
parameter is applied, then this parameter should be no more than the maximum number of rows in the groups.  If the range provided to the function exceeds the limits of the dataset, then the function generates a null value.
 If the range of the function is valid but includes missing values, the function generates a missing, nonnull value.
Usage Notes:
Required?  Data Type  Example Value 

Yes  Integer  4 
Examples
Example  Examine prior order history
The following dataset contains order information for the preceding 12 months. You want to compare the current month's average against the preceding quarter.
Source:
Date  Amount 

12/31/15  118 
11/30/15  6 
10/31/15  443 
9/30/15  785 
8/31/15  77 
7/31/15  606 
6/30/15  421 
5/31/15  763 
4/30/15  305 
3/31/15  824 
2/28/15  135 
1/31/15  523 
Transform:
Using the ROLLINGAVERAGE
function, you can generate a column containing the rolling average of the current month and the two previous months:
window value: ROLLINGAVERAGE(Amount, 3, 0) order: Date
Note the sign of the second parameter and the order
parameter. The sort is in the reverse order of the Date
parameter, which preserves the current sort order. As a result, the second parameter, which identifies the number of rows to use in the calculation, must be positive to capture the previous months.
Technically, this computation does not capture the prior quarter, since it includes the current quarter as part of the computation. You can use the following column to capture the rolling average of the preceding month, which then becomes the true rolling average for the prior quarter. The window
column refers to the name of the column generated from the previous step:
window value: NEXT(window, 1) order: Date
Note that the order parameter must be preserved. This new column, window1
, contains your prior quarter rolling average:
rename col:window1 to:'Amount_PriorQtr'
You can reformat this numeric value:
set col:Amount_PriorQtr value:NUMFORMAT(Amount_PriorQtr, '###.00')
You can use the following transform to calculate the net change. This formula computes the change as a percentage of the prior quarter and then formats it as a twodigit percentage.
derive type:single value:NUMFORMAT(((Amount  Amount_PriorQtr) / Amount_PriorQtr) * 100, '##.##') as:'NetChangePct_PriorQtr'
Results:
NOTE: You might notice that there are computed values for Amount_PriorQtr
for February and March. These values do not factor in a full three months because the data is not present. The January value does not exist since there is no data preceding it.
Date  Amount  Amount_PriorQtr  NetChangePct_PriorQtr 

12/31/15  118  411.33  71.31 
11/30/15  6  435.00  98.62 
10/31/15  443  489.33  9.47 
9/30/15  785  368.00  113.32 
8/31/15  77  596.67  87.1 
7/31/15  606  496.33  22.1 
6/30/15  421  630.67  33.25 
5/31/15  763  421.33  81.09 
4/30/15  305  494.00  38.26 
3/31/15  824  329.00  150.46 
2/28/15  135  523.00  .74.19 
1/31/15  523 
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