debug_print_raw_parse

debug_print_raw_parse — Logs each query’s raw parse tree. Observed in PG19 Beta 3; its last measured boot default is off in PG19 Beta 3, with user context. This is a beta-snapshot fact and can change before PostgreSQL 19 GA.

Note

Fact — official short description: “Logs each query’s raw parse tree.”

Identity

Type , Valuebool: Upstream pg_settings type
Context , Valueuser: Settable by an ordinary user
Unit , Value—: Raw unit
Range , Value—: Raw limits in the last observed version
Enum values , Value—: — for non-enum types
Category , ValueReporting and Logging / What to Log: Upstream classification
Latest boot value , Valueoff: off

Lifecycle

Fact	Value
First observed	PG19 Beta 3
Present in	PG19 Beta 3
Removed in	No
Introduction commit	`06473f5a344d` — Allow to log raw parse tree.
Commit date	2025-09-06
Discussion	thread 1

Default history

Measured PG9.0–19 Beta 3 boot defaults
Versions	Raw `boot_val`	Unit	Human value
PG19 Beta 3	`off`	—	off

How it works

PostgreSQL describes debug_print_raw_parse as follows: “Logs each query’s raw parse tree.” It can be changed per session, which makes plan or behavior comparisons possible without changing every workload. The atlas measures it in PG19 Beta 3; boot_val is the compiled or initialized baseline, not proof of a running cluster’s effective setting.

The raw parse tree is emitted before parse analysis, rewriting, planning, and execution. Messages use LOG level; debug_pretty_print changes formatting, while client_min_messages and log_min_messages determine where they are visible. Output can be very large and can expose query text structure.

Read it together with debug_print_parse, debug_print_rewritten, debug_print_plan, debug_pretty_print. Check SHOW and pg_settings on the target server, verify the source and pending_restart fields, and compare workload, logs, and resource metrics before and after any change.

Tuning advice

Tip

Advice. These are workload-specific starting points and must be validated with measurements.

Workload	Guidance
OLTP	Keep the upstream default until a reproducible operational need is demonstrated. Test under representative concurrency and inspect logs, latency, and the related settings before changing cluster-wide policy.
OLAP	Evaluate the setting with representative long-running and batch work. Measure total runtime, resource use, log volume, and failure behavior across the whole job rather than one isolated operation.
Small nodes	Minimize overrides and document rollback. A small system has less room for extra logging, workers, memory, or retained WAL, so validate the change with explicit resource limits.

Pigsty

Values use the fixed 8-vCPU, 32-GiB, 100-GiB SSD fixture and render the current Pigsty templates for PG19 Beta 3; this does not assert current Pigsty support for that historical or beta release.

Template	Effective value	Versus upstream boot	Source expression
OLTP	Unmodified	—	—
OLAP	Unmodified	—	—
CRIT	Unmodified	—	—
TINY	Unmodified	—	—

Caution

Advice — pending human review. Fact from the current Pigsty template projection: OLTP: PG19 Beta 3 unmodified; OLAP: PG19 Beta 3 unmodified; CRIT: PG19 Beta 3 unmodified; TINY: PG19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

Common pitfalls

Treating the measured boot_val for debug_print_raw_parse as proof of the effective value on an initialized or managed cluster.
Applying a change as though it were immediate while pg_settings reports user context.
Changing this setting in isolation without checking the linked limits, observability, and rollback path.
Depending on beta behavior in production without retesting the PostgreSQL 19 final release.

debug_print_parse · debug_print_rewritten · debug_print_plan · debug_pretty_print · log_min_messages