$join¶
Allows joining a variable value to another variable value that provides a entity identifier. The current object is a value set. $join will access to a variable value within this value set.
See also $, $val, $value.
Syntax¶
$join(name,idname[,flat])
Parameter | Description |
---|---|
name |
The name of the variable from which the value shall be retrieved. |
idname |
The name of the variable from which the entity identifier shall be retrieved. |
flat |
Specifies that if in case of the join operation result in a value sequence tree, the result should be flatten in a sequence of unique values.
Default is false and a value sequence tree will be transformed into a sequence of comma separated stringified values.
|
Examples¶
Returns the BRAND_NAME of a medication which is identified by the MEDICATION_ID.
$join('medications.Drugs:BRAND_NAME','MEDICATION_ID')
Given the following datasets, a table with a repeatable variable named code:
ID | code |
---|---|
aa | Acode1,Acode2 |
bb | Acode1 |
cc | Acode3 |
dd |
and code_mapper a table with a repeatable variable parent:
ID | parent |
---|---|
Acode1 | Bcode1,Bcode2 |
Acode2 | Bcode1,Bcode3 |
Acode3 |
The following script:
$join('test.code_mapper:parent','code', true)
will return the following value sequences:
D | flat |
---|---|
aa | Bcode1,Bcode2,Bcode3 |
bb | Bcode1,Bcode2 |
cc | |
dd |
Without the flat option, the following script:
$join('test.code_mapper:parent','code')
would return the following value sequencies where value sequencies of second order have been stringified:
D | non-flat |
---|---|
aa | “Bcode1,Bcode2”,”Bcode1,Bcode3” |
bb | “Bcode1,Bcode2” |
cc | |
dd |