Usage of LAG function in Oracle BIP's child data set - Any Limitations?

Summary

Usage of LAG function in Oracle BIP's child data set - Any Limitations?

Content

Hello,

I am trying to LAG function in a child dataset of Oracle BIP but it gives an 'ORA-01722: invalid number'. And if I execute the data-model on its own as Parent, it works fine.

Can anyone please help me with a wokaround? Or is there a limitation to use LAG function in child-datamodel of BIP?

thanks,

Santosh

Version

Release 13 18c