COUNT
Use this function to retrieve the number of instances for the specified entities or attributes. Please note the similar function SIZE.
Syntax | Code Block |
|---|
COUNT ( collection ) |
Input
Return type
Examples Suppose the following data model.
| Instance | Person.name |
|---|
| 1 | “John” | | 2 | “Dave” | | 3 | “Jane” | | 4 | “Lisa” |
| Instance | House.rooms |
|---|
| singleton | “living room”, “bathroom”, “bedroom” |
| Expression | Result | Type |
|---|
| COUNT ( ALL Person ) | 4 | Integer | | COUNT ( House.rooms ) | 3 | Integer | | COUNT ( ALL Person + ALL House ) | 5 | Integer | | COUNT ( COLLECT Person FROM ALL Person WHERE ( Person.name = “Lisa” ) ) | 1 | Integer | | COUNT ( ? (= UNKNOWN) ) | UNKNOWN | Integer |
| UI Text Box |
|---|
| SIZE and COUNT are similar except for ?: SIZE( ? ) results in 0, while COUNT( ? ) results in ? |
|