I am calling API v2 to retrieve the messages from Lithium, what I want is to retrieve only the messages whose last_edit_time is greater than a value. I see only the post_time can be used in the where condition. Any idea to get only the new messages which is updated/edited recently?
At this moment you can't use the current_revision.last_edit_time as a constraint in your LIQL queries. This is not supported by Lithium's APIv2.
As Tariq pointed out this restriction is currently not supported in LiQL. I'd recommend to submit a product enhancement idea as I can see how it could be useful, particularly for TKB scenarios.
I'm curious what the scenario is that you would use it in, @TalendCommunity?
If you want to replicate and perform analysis on larger sections of community data in your own warehouse I would recommend you use the Lithium Bulk Data API to pull the necessary elements into your own DWH.