# pg_stats_sampling

Get a random sample of rows. Use sampleSize for exact row count (any method), or percentage for approximate sampling with bernoulli/system methods.

Agent View of the PolicyLayer registry record for `pg_stats_sampling`. HTML page: https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-stats-sampling

## Facts

- Tool: `pg_stats_sampling`
- Server: PostgreSQL MCP Server (`@neverinfamous/postgres-mcp`) — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp.md
- Install: `npx -y @neverinfamous/postgres-mcp`
- Homepage: https://github.com/neverinfamous/postgresql-mcp.git
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "pg_stats_sampling",
    "arguments": {}
  }
}
```

## Why pg_stats_sampling is rated Low

This tool retrieves a subset of rows from a PostgreSQL table for analysis purposes. It performs a SELECT operation with sampling logic (TABLESAMPLE or similar), which reads data without side effects. No data is created, modified, deleted, or executed. The blast radius of misuse is limited to information disclosure of sampled data, which is low severity.

From the tool's own definition: "Tool description states 'Get a random sample of rows' with parameters for sampleSize and percentage, indicating data retrieval with no modification or deletion."

## Use case

AI agents call pg_stats_sampling to retrieve information from PostgreSQL MCP Server without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches PostgreSQL MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "pg_stats_sampling": {}
  }
}
```

## Other tools on PostgreSQL MCP Server (273)

- `pg_cascade_simulator` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cascade-simulator.md
- `pg_cron_cleanup_history` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cron-cleanup-history.md
- `pg_cron_unschedule` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cron-unschedule.md
- `pg_detach_partition` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-detach-partition.md
- `pg_doc_drop_collection` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-doc-drop-collection.md
- `pg_doc_remove` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-doc-remove.md
- `pg_drop_index` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-drop-index.md
- `pg_drop_schema` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-drop-schema.md
- `pg_drop_sequence` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-drop-sequence.md
- `pg_drop_table` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-drop-table.md
- `pg_drop_view` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-drop-view.md
- `pg_kcache_reset` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-kcache-reset.md
- `pg_migration_rollback` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-migration-rollback.md
- `pg_partman_set_retention` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-partman-set-retention.md
- `pg_reset_stats` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-reset-stats.md
- `pg_role_drop` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-role-drop.md
- `pg_text_normalize` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-text-normalize.md
- `pg_truncate` — Destructive — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-truncate.md
- `pg_analyze` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-analyze.md
- `pg_analyze_query_indexes` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-analyze-query-indexes.md
- `pg_buffer` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-buffer.md
- `pg_cancel_backend` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cancel-backend.md
- `pg_cluster` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cluster.md
- `pg_cron_create_extension` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cron-create-extension.md
- `pg_cron_schedule` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cron-schedule.md
- `pg_cron_schedule_in_database` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-cron-schedule-in-database.md
- `pg_explain_analyze` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-explain-analyze.md
- `pg_geo_cluster` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-geo-cluster.md
- `pg_geo_transform` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-geo-transform.md
- `pg_geometry_transform` — Execute — https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp/pg-geometry-transform.md
- …and 243 more: https://policylayer.com/tools/io-github-neverinfamous-postgres-mcp.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-neverinfamous-postgres-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-neverinfamous-postgres-mcp
