ktx/examples/postgres-historic/README.md

Postgres Query History Example

This example is a manual smoke for Postgres query-history ingest through pg_stat_statements. It starts Postgres 14 with the extension preloaded, generates query workload under separate users, runs ktx setup with --enable-query-history, and verifies the staged query-history artifacts:

• manifest.json
• tables/*.json
• patterns-input.json as the full audit input
• patterns-input/part-*.json as bounded pattern WorkUnit shards

The smoke also runs the same workload twice and verifies the second stage-only run has workUnitCount: 0, which proves unchanged bucketed table inputs and unchanged bounded pattern shards do not schedule LLM work.

Prerequisites

• Docker with Compose v2
• Node and pnpm matching the KTX workspace
• uv on PATH so the KTX-managed Python runtime can install the bundled runtime wheel

Run

From the KTX repository root:

examples/postgres-historic/scripts/smoke.sh

The smoke creates a temporary KTX project, isolates the managed Python runtime under the temporary project parent, starts Postgres on 127.0.0.1:55432, and uses this connection URL:

postgresql://ktx_reader:ktx_reader@127.0.0.1:55432/analytics # pragma: allowlist secret

Set KTX_POSTGRES_HISTORIC_KEEP_DOCKER=1 to leave the container running after the script exits.

The smoke validates the query-history raw snapshot path without requiring LLM credentials. It uses KTX's local stage-only ingest API after ktx setup, so the deterministic reader, batch SQL parser, stable artifact writer, and diff-based WorkUnit planning are checked independently from curation.

Manual Commands

Start Postgres and generate the base workload:

docker compose -f examples/postgres-historic/docker-compose.yml up -d --wait
examples/postgres-historic/scripts/generate-workload.sh base

Create a project and enable query history:

export WAREHOUSE_DATABASE_URL=postgresql://ktx_reader:ktx_reader@127.0.0.1:55432/analytics # pragma: allowlist secret
pnpm --filter @kaelio/ktx run build
node packages/cli/dist/bin.js --project-dir /tmp/ktx-postgres-historic setup \
  --new \
  --skip-agents \
  --skip-llm \
  --skip-embeddings \
  --skip-sources \
  --database postgres \
  --new-database-connection-id warehouse \
  --database-url env:WAREHOUSE_DATABASE_URL \
  --database-schema public \
  --enable-query-history \
  --query-history-min-executions 2 \
  --yes \
  --no-input

Readiness check

pnpm run ktx -- status --project-dir /tmp/ktx-postgres-historic --no-input

The installed CLI form is:

ktx status --project-dir /tmp/ktx-postgres-historic --no-input

Expected output includes PASS Postgres query history (warehouse) when pg_stat_statements is installed, pg_read_all_stats is granted, and tracking is enabled. A low pg_stat_statements.max value is reported as an informational note, not a warning.

Run query-history ingest:

pnpm run ktx -- ingest warehouse --project-dir /tmp/ktx-postgres-historic \
  --query-history \
  --no-input

The public query-history ingest path also runs curation WorkUnits, so it requires a configured LLM provider.

Inspect the latest manifest:

find /tmp/ktx-postgres-historic/raw-sources/warehouse/historic-sql -name manifest.json | sort | tail -n 1

The manifest should have source: "historic-sql", dialect: "postgres", positive snapshotRowCount, positive touchedTableCount, numeric parseFailures, warnings, and probeWarnings. The same directory should contain patterns-input.json, at least one patterns-input/part-*.json pattern shard for cross-table candidates, and one tables/*.json file per touched table.

Troubleshooting

• Missing extension: confirm shared_preload_libraries=pg_stat_statements and CREATE EXTENSION pg_stat_statements; both happened in the analytics database.
• Missing grants: confirm GRANT pg_read_all_stats TO ktx_reader;.
• Empty snapshot: rerun scripts/generate-workload.sh base and keep --query-history-min-executions 2 for the smoke.
• SQL-analysis failures: run pnpm run ktx -- dev runtime status from the KTX repository root and confirm uv, the bundled Python wheel, and the managed runtime all pass.