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Inspect the database

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This guide explains how to read live database statistics using the CLI, MCP, or Explorer.

Read database statistics from:

Use this page to:

To pick up a signal from these checks, see Detecting. For the other sources, see Observability.

Using the CLI

The Supabase CLI reads live statistics from Postgres internals. Most commands work on any Postgres database, not only a Supabase project.

The inspect db command

The inspection tools for your Postgres database are under the inspect db command. You can get a full list of available commands by running supabase inspect db help.

$ supabase inspect db help
Tools to inspect your Supabase database

Usage:
  supabase inspect db [command]

Available Commands:
  bloat                Estimates space allocated to a relation that is full of dead tuples
  blocking             Show queries that are holding locks and the queries that are waiting for them to be released
  cache-hit            Show cache hit rates for tables and indices

...

Connect to any Postgres database

Most inspection commands are Postgres agnostic. You can run inspection routines on any Postgres database even if it is not a Supabase project by providing a connection string via --db-url.

For example you can connect to your local Postgres instance:

supabase inspect db bloat --db-url postgresql://postgres:postgres@localhost:5432/postgres

Connect to a Supabase instance

Working with Supabase, you can link the Supabase CLI with your project:

supabase link --project-ref <project-id>

Then the CLI will automatically connect to your Supabase project whenever you are in the project folder and you no longer need to provide --db-url.

Inspection commands

Below are the db inspection commands provided, grouped by different use cases.

Note

Some commands might require pg_stat_statements to be enabled or a specific Postgres version to be used.

Disk storage

These commands are handy if you are running low on disk storage:

Query performance

The commands below are useful if your Postgres database consumes a lot of resources like CPU, RAM or Disk IO. You can also use them to investigate slow queries.

  • cache-hit - shows how efficient your cache usage is overall
  • unused-indexes - shows indexes with low index scans
  • index-usage - shows information about the efficiency of indexes
  • seq-scans - show number of sequential scans recorded against all tables
  • long-running-queries - shows long running queries that are executing right now
  • outliers - shows queries with high execution time but low call count and queries with high proportion of execution time spent on synchronous I/O

Locks

  • locks - shows statements which have taken out an exclusive lock on a relation
  • blocking - shows statements that are waiting for locks to be released

Connections

  • role-connections - shows number of active connections for all database roles (Supabase-specific command)
  • replication-slots - shows information about replication slots on the database

Using SQL

Open Explorer, select Run SQL, and choose Database as the query source. You can also run read-only diagnostics through MCP execute_sql.

Use Performance checks for active sessions, blockers, expensive statements, and cache hit rates. Use Capacity checks for relation sizes and connection counts.

pg_stat_activity is a live snapshot. pg_stat_statements and cache counters are cumulative since their last reset; they do not describe an arbitrary historical window. Compare saved snapshots with the same reset interval when measuring changes. Check the pg_stat_statements guide for extension requirements.

When a check identifies a statement, inspect its query plan. A long-running session or high cumulative query time is evidence to investigate, not a reason by itself to cancel a query or reset statistics.

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