What is the difference between text and pg_catalog.text?
They are the same thing in a default installation.

pg_catalog.text is the schema-qualified version of the type name text.

The search_path always contains pg_catalog automatically. Per documentation:


  In addition to public and user-created schemas, each database contains
  a pg_catalog schema, which contains the system tables and all the
  built-in data types, functions, and operators. pg_catalog is always
  effectively part of the search path. If it is not named explicitly in
  the path then it is implicitly searched before searching the path's
  schemas. This ensures that built-in names will always be findable.
  However, you can explicitly place pg_catalog at the end of your search
  path if you prefer to have user-defined names override built-in names.


Bold emphasis mine. If you do such a thing, Postgres will automatically start schema-qualifying names in text-representation, that would otherwise be resolved differently. That's most probably what you see. Check your current search_path with:

SHOW search_path;


Closely related:


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