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Supabase

What are the sql commands, to obtain the description of a project including tables with keys, restrictions and relationships, etc. Thank you

There are no SQL commands for this, this information is stored in Supabase's own DB and not the one hosted for you

Also some of these things are on a table to table basis

Not sure what you mean by keys? as in primary keys?

thank you, https://github.com/zernonia/supabase-schemasolves something, I like how it creates the diagram. On the other hand I remembered ** show <table> ** from mysql, which is clear to me that it is not easy.

SELECT * FROM pg_catalog.pg_tables;
--  where schemaname = 'public';

  SELECT 
   table_name, 
   column_name, 
   data_type 
FROM 
   information_schema.columns
WHERE 
   table_name = 'posts';