Returns the first n members or tuples present in a set.
Syntax
Head ( set [,numeric value expression ] )
Parameter | Description |
---|---|
The set from which to take items. | |
numeric value expression | The count of items to take from the beginning of the set. If omitted, the default is 1. If less than 1, an empty set is returned. If the value exceeds the number of tuples in the input set, the original set is returned. |
Example
This example uses the following part of the Sample Basic outline:
The following expression
[Product].children
returns the set:
{ [100], [200], [300], [400], [Diet] }
Therefore, the following expression
Head ( [Product].children, 2)
returns the first two members of the previous result set:
{ [100], [200] }
This example uses the following parts of the Sample Basic outline:
The following expression
CrossJoin ( [100].children, [South].children )
returns the set:
{ ([100-10], Texas), ([100-10], Oklahoma), ([100-10], Louisiana), ([100-10], [New Mexico]), ([100-20], Texas), ([100-20], Oklahoma), ([100-20], Louisiana), ([100-20], [New Mexico]), ([100-30], Texas), ([100-30], Oklahoma), ([100-30], Louisiana), ([100-30], [New Mexico]) }
And the following expression
Head ( CrossJoin ([100].children, [South].children), 8 )
returns the first 8 tuples of the previous result set:
{ ([100-10], Texas), ([100-10], Oklahoma), ([100-10], Louisiana), ([100-10], [New Mexico]), ([100-20], Texas), ([100-20], Oklahoma), ([100-20], Louisiana), ([100-20], [New Mexico]) }
Additionally, the following expression
([Year].generations(2).members)
returns the set of members comprising the second generation of the Year dimension:
{ [Qtr1], [Qtr2], [Qtr3], [Qtr4] }
Therefore, the following query
SELECT {([Year].generations(2).members)} ON COLUMNS, Head ( CrossJoin ( [100].children, [South].children), 8 ) ON ROWS FROM Sample.Basic
returns the grid:
(axis) | Qtr1 | Qtr2 | Qtr3 | Qtr4 | |
---|---|---|---|---|---|
100–10 | Texas | 489 | 536 | 653 | 547 |
Oklahoma | 87 | 92 | 128 | 211 | |
Louisiana | 93 | 106 | 128 | 137 | |
New Mexico | 76 | 101 | 122 | 70 | |
100–20 | Texas | 206 | 199 | 152 | 82 |
Oklahoma | 84 | 66 | 55 | 79 | |
Louisiana | 119 | 158 | 171 | 104 | |
New Mexico | –103 | –60 | –98 | –18 |
See Also