FirstSortedValue - chart function
FirstSortedValue() returns the value from the expression specified in value that corresponds to the result of sorting the sort_weight argument, taking into account rank, if specified. If more than one resulting value shares the same sort_weight for the specified rank, the function returns NULL.
Syntax:
FirstSortedValue([{SetExpression}] [DISTINCT] [TOTAL [<fld {,fld}>]] value, sort_weight [,rank])
Return data type: dual
Arguments:
| value | Output field. The function finds the value of the expression value that corresponds to the result of sorting sort_weight. |
| sort_weight | Input field. The expression containing the data to be sorted. The first (lowest) value ofsort_weight is found, from which the corresponding value of the value expression is determined. If you place a minus sign in front of sort_weight, the function returns the last (highest) sorted value instead. |
| rank | By stating a rank "n" larger than 1, you get the nth sorted value. |
| SetExpression | By default, the aggregation function will aggregate over the set of possible records defined by the selection. An alternative set of records can be defined by a set analysis expression. |
| DISTINCT | If the word DISTINCT occurs before the function arguments, duplicates resulting from the evaluation of the function arguments are disregarded. |
| TOTAL | If the word TOTAL occurs before the function arguments, the calculation is made over all possible values given the current selections, and not just those that pertain to the current dimensional value, that is, it disregards the chart dimensions. The TOTAL qualifier may be followed by a list of one or more field names within angle brackets <fld>. These field names should be a subset of the chart dimension variables. See: Defining the aggregation scope |
Examples and results:
| Customer | Product | UnitSales | UnitPrice |
|---|
| Astrida | AA | 4 | 16 |
| Astrida | AA | 10 | 15 |
| Astrida | BB | 9 | 9 |
| Betacab | BB | 5 | 10 |
| Betacab | CC | 2 | 20 |
| Betacab | DD | - | 25 |
| Canutility | AA | 8 | 15 |
| Canutility | CC | - | 19 |
| firstsortedvalue (Product, UnitPrice) | BB, which is the Productwith the lowest UnitPrice(9). |
| firstsortedvalue (Product, UnitPrice, 2) | BB, which is the Productwith the second-lowest UnitPrice(10). |
| firstsortedvalue (Customer, -UnitPrice, 2) | Betacab, which is the Customerwith the Product that has second-highestUnitPrice(20). |
| firstsortedvalue (Customer, UnitPrice, 3) | NULL, because there are two values of Customer (Astrida and Canutility) with the samerank (third-lowest) UnitPrice(15). Use the distinct qualifier to make sure unexpected null results do not occur. |
| firstsortedvalue (Customer, -UnitPrice*UnitSales, 2) | Canutility, which is the Customer with the second-highest sales order value UnitPrice multiplied by UnitSales (120). |
Data used in examples:
ProductData:
LOAD * inline [
Customer|Product|UnitSales|UnitPrice
Astrida|AA|4|16
Astrida|AA|10|15
Astrida|BB|9|9
Betacab|BB|5|10
Betacab|CC|2|20
Betacab|DD||25
Canutility|AA|8|15
Canutility|CC||19
] (delimiter is '|');
