Is it possible to use CrateDB with a PostgreSQL database by using Foreign Data Wrapper?

Is it possible to use CrateDB from within a PostgreSQL database by using Foreign Data Wrapper? Normally PostgreSQL allows to connect to some other databases by creating foreign data wrappers, as described in:

(Assuming this is possible) Do you have any suggestions/recommendations if I want to query CrateDB tables from a PostgreSQL database?

Currently this is unfortunately not supported.

We have tested connecting from PG to CrateDB using FDW, however it seems like for using postgresql_fdw we miss Cursor support, which might be integrated with 4.8 (but still with a big question mark) also see Add DECLARE CURSOR support · Issue #10212 · crate/crate · GitHub

With using the more generic odbc_fdw there are currently problems with passing down query parameters resulting in PG trying to load complete tables from CrateDB

We are also investigating the other direction (i.e. allowing querying a pg instance from within CrateDB, but no concrete plans for that yet.

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