fdw_invalid_data_type_descriptors (SQLSTATE HV006) occurs when a PostgreSQL foreign table column uses a data type that does not match the remote column’s descriptor.
fdw_invalid_data_type_descriptors appears when PostgreSQL detects mismatched data types between a foreign table and the underlying remote table. Align the column types with ALTER FOREIGN TABLE ... ALTER COLUMN or add explicit CAST clauses on the foreign server to resolve the error.
PostgreSQL Error HV006
fdw_invalid_data_type_descriptors is a PostgreSQL error with SQLSTATE code HV006 that signals a mismatch between the local foreign table column definition and the remote column’s data type descriptor.
The error fires during SELECT, INSERT, UPDATE, COPY, or ANALYZE operations that rely on the foreign data wrapper (FDW) to map local columns to the remote schema.
The FDW validates column descriptors when it prepares or executes a statement.
If a local column is defined as VARCHAR but the remote column is NUMERIC, PostgreSQL raises HV006 immediately.
Type promotion rules do not apply across servers, so any difference in length modifiers, nullability, or numeric precision can trigger the error.
First compare the local foreign table DDL to the remote table DDL. Align the data types exactly, including length, precision, and scale.
Apply ALTER FOREIGN TABLE ...
ALTER COLUMN SET DATA TYPE on the local side, or change the remote table with ALTER TABLE if you control the source.
Legacy schemas often store flags as CHAR(1) remotely but BOOLEAN locally. Change the local definition to CHAR(1) or CAST the remote expression to BOOLEAN in the foreign table OPTIONS clause.
Cross-database migrations sometimes compress text with TEXT on one side and VARCHAR(n) on the other.
Use TEXT on both ends to avoid constant length verification failures.
Always create foreign tables with CREATE FOREIGN TABLE ... OPTIONS (schema_name, table_name) AS SELECT * FROM ...
syntax in tools like Galaxy to pull exact metadata.
Add regression tests that run ANALYZE on foreign tables in staging to surface mismatches before promotion to production.
HV004 (fdw_invalid_column_name) occurs when column names differ; fix by renaming local columns.
HV007 (fdw_invalid_column_name_descriptors) signals incompatible column options; recreate the foreign table with matching options.
.
Yes. PostgreSQL requires identical base type and modifiers across FDW boundaries. Even VARCHAR vs. TEXT can fail.
No. The error happens before execution. You must align the descriptor at table definition time or change the remote schema.
No. Any FDW that validates descriptors, including oracle_fdw or mysql_fdw, can raise HV006.
Galaxy’s schema-aware AI copilot introspects both local and remote tables, suggesting CREATE FOREIGN TABLE statements with perfectly matched types, preventing HV006 up front.
.avif)
.avif){kind=logo}
