Building or modifying a Foreign Data Wrapper (FDW) — the SQL/MED interface for accessing external data as if it were PG tables. Covers the FdwRoutine callback set (GetForeignRelSize / GetForeignPaths / GetForeignPlan / BeginForeignScan / IterateForeignScan / ReScanForeignScan / EndForeignScan for scans, BeginForeignInsert / ExecForeignInsert / ... for DML), the postgresfdw reference implementation, plan pushdown (WHERE / JOIN / AGG / LIMIT), extended-explain support, and the FDW-related core code (src/backend/foreign/foreign.c, foreign-table catalog, user mappings). Loads when the user asks about writing an FDW, CREATE FOREIGN TABLE, why postgresfdw is fast, pushdown decisions (useremoteestimate, fdwstartupcost), user mappings and password security (passwordrequired), the loopback-back-to-self bypass-RLS pattern from postgresfdw, or adding a new pushdown-shape. Skip when the ask is about specific non-postgresfdw wrappers (filefdw, oraclefdw external, mysqlfdw external) — those are separate implementations.
Install with
Claude CodeCodexCursorGitHub CopilotGemini CLI
Supported by the Atlas install prompt. Skill-specific requirements vary.
Skill stats
Skills1CategorySecurityStars0
About this skill
Building or modifying a Foreign Data Wrapper (FDW) — the SQL/MED interface for accessing external data as if it were PG tables. Covers the FdwRoutine callback set (GetForeignRelSize / GetForeignPaths / GetForeignPlan / BeginForeignScan / IterateForeignScan / ReScanForeignScan / EndForeignScan for scans, BeginForeignInsert / ExecForeignInsert / ... for DML), the postgresfdw reference implementation, plan pushdown (WHERE / JOIN / AGG / LIMIT), extended-explain support, and the FDW-related core code (src/backend/foreign/foreign.c, foreign-table catalog, user mappings). Loads when the user asks about writing an FDW, CREATE FOREIGN TABLE, why postgresfdw is fast, pushdown decisions (useremoteestimate, fdwstartupcost), user mappings and password security (passwordrequired), the loopback-back-to-self bypass-RLS pattern from postgresfdw, or adding a new pushdown-shape. Skip when the ask is about specific non-postgresfdw wrappers (filefdw, oraclefdw external, mysqlfdw external) — those are separate implementations.
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Building or modifying a Foreign Data Wrapper (FDW) — the SQL/MED interface for accessing external data as if it were PG tables. Covers the `FdwRoutine` callback set (`GetForeignRelSize` / `GetForeignPaths` / `GetForeignPlan` / `BeginForeignScan` / `IterateForeignScan` / `ReScanForeignScan` / `EndForeignScan` for scans, `BeginForeignInsert` / `ExecForeignInsert` / … for DML), the `postgres_fdw` reference implementation, plan pushdown (WHERE / JOIN / AGG / LIMIT), extended-explain support, and the FDW-related core code (`src/backend/foreign/foreign.c`, foreign-table catalog, user mappings). Loads when the user asks about writing an FDW, `CREATE FOREIGN TABLE`, why postgres_fdw is fast, pushdown decisions (`use_remote_estimate`, `fdw_startup_cost`), user mappings and password security (`password_required`), the loopback-back-to-self bypass-RLS pattern from postgres_fdw, or adding a new pushdown-shape. Skip when the ask is about specific non-postgres_fdw wrappers (file_fdw, oracle_fdw external, mysql_fdw external) — those are separate implementations.
About this listing
Category
Security
Reported license
PostgreSQL
Listing language (estimated)
English
Review status
Not individually reviewed
Agent compatibility
Atlas installation supports Claude Code, Codex, and Cursor. Skill-specific dependencies and features are checked during setup.
Claude Code
Codex
Cursor
GitHub Copilot
Gemini CLI