HV001ERRORTier 2 — Caution✅ HIGH confidenceFDW out of memory
Category: Foreign Data Wrapper ErrorVersions: All Postgres versions (with FDW extension)
What this means
SQLSTATE HV001 is raised when a foreign data wrapper cannot allocate sufficient memory to perform its operation.
Why it happens
- 1The FDW process exhausts available memory while processing a large foreign table query
How to reproduce
FDW memory exhaustion on a large query.
trigger — this will ERROR
ERROR: foreign-data wrapper memory allocation failed
Fix 1: Reduce the result set from the foreign table query
When HV001 appears on foreign table queries.
fix
SELECT * FROM foreign_table WHERE date > CURRENT_DATE - 30 LIMIT 1000;Why this works
Adding WHERE conditions and LIMIT reduces the amount of data the FDW must buffer in memory.
Fix 2: Increase work_mem for the session
When the operation genuinely requires more memory.
fix
SET work_mem = '256MB';Why this works
Increasing work_mem allows the FDW to use more memory for sorting and buffering foreign data.
Sources
📚 Official docs: https://www.postgresql.org/docs/current/errcodes-appendix.html
🔧 Source ref: Class HV — Foreign Data Wrapper Error
Confidence assessment
✅ HIGH confidence
Standard SQLSTATE for FDW memory errors. Stable across versions.
See also
🔗 Related errors
📄 Reference pages
postgres_fdwwork_mem
⚙️ This error reference was generated with AI assistance and reviewed for accuracy. Examples are provided to illustrate common scenarios and may not cover every case. Always test fixes in a development environment before applying to production. Spotted an error? Suggest a correction →