count()
Function count() calculates the number of rows in an alias (ignoring the rows that are null). Only one row from the alias will be kept after this function is called, and all the rest rows will be abandoned.
Arguments：
Returns：
Sample graph: (to be used for the following examples)
Run below UQLs one by one in an empty graphset to create graph data:
```customlang___fold__lang_uql
create().node_schema("professor").node_schema("student")
create().node_property(@*, "age", int32).node_property(@*, "email", string)
insert().into(@professor).nodes([{_id:"P001",_uuid:1,age:53,email:"
[email protected]"},{_id:"P002",_uuid:2,age:27,email:"
[email protected]"}])
insert().into(@student).nodes([{_id:"S001",_uuid:3,age:27,email:"
[email protected]"},{_id:"S002",_uuid:4,age:20,email:"
[email protected]"},{_id:"S003",_uuid:5,age:25,email:"
[email protected]"}])
```
Common Usage
Example: Calculate the number of all nodes in the graph
find().nodes() as n
return count(n)
