Hi All
I have two tables from a postgres DB , how do I create the mapping between this two tables in the metabse SQL script . I need to do left join to make the filter work .
Thanks in advance
You want to look at configuration of metadata in the 
Admin Guide in particular setup of Entity Key and Foreign Key in the types section.
If you configure this you can filter and group etc. on fields across your two tables and it becomes part of the user interface for building questions so it’s more user friendly to people who don’t know SQL.
If that’s not what you want you can still use native SQL - but then knowledge needed is not linked to Metabase - but more a google for your particular database like e.g. “Postgres left join”