Only() returns a value if there is one and only one possible result from the aggregated data. If the records within each grouped result as defined by the group by clause contains only one value, then that value is returned. Otherwise NULL is returned
Return data type: dual
|expr||The expression or field containing the data to be measured.|
Examples and results:
Add the example script to your document and run it. Then add, at least, the fields listed in the results column to a sheet in our document to see the result.
LOAD * inline [
] (delimiter is '|');
LOAD Customer, Only(CustomerID) as MyUniqIDCheck Resident Temp Group By Customer;
because only customer Astrida has complete records that include CustomerID.