How old does PostgreSQL hold the tableau metadata? Does it get wiped out after certain days? if yes, Does all tables in Tableau PostgreSQL do the same or is it limited to certain tables.
E.g- Does any table in Tableau PostgreSQL hold data only for last X days?
It may not address all your questions but a good starting point would be the following link:
Create Custom Administrative Views:
The four bullet points near the bottom of the page call out the data retention period for a number of tables.
Retrieving data ...