Table Properties "_timescaledb_cache" , _timescaledb_catalog, _timescaledb_internal" What are those doing?

Question

Does anyone know what those settings are doing?Unlikely I couldn't find something that helps me understand this in Google. It is in Table Properties->Schema:

• _timescaledb_cache
• _timescaledb_catalog
• _timescaledb_internal

Answer 1

Those are internal schemas used by the TimescaleDB extension, for cache/catalog/internal functions and tables. They're needed for the correct functioning of the extension. They are installed when the extension is installed and will be removed if you drop the extension (along with everything else about the extension, including your data if it's in a hypertable and you run the command with cascade). See https://github.com/timescale/timescaledb/blob/master/sql/pre_install/schemas.sql for where they're installed. They have different uses within the codebase and house different types of functions/tables.