chmonitor

Browse every database, table, column, index, projection, and dependency in your ClickHouse instance without writing SQL.

Routes/explorer
Feature idtables
Default accesspublic
Requires authNo (set CHM_FEATURE_TABLES_ACCESS=authenticated to gate)
System tablessystem.databases, system.tables, system.columns, system.projection_parts, system.data_skipping_indices, system.dictionaries
ClickHouse grantsSELECT on the system tables above

What it does

The Data Explorer provides a tree-browser for the entire schema of a ClickHouse host. Select a database from the sidebar, then a table, to see:

  • Column list — name, type, and whether the column is part of the primary key, sorting key, or partition key.
  • DDL — the CREATE TABLE statement for the selected table.
  • Indexes — partition key, sorting key, primary key, sampling key, and engine parameters.
  • Skip indexes — data-skipping index definitions.
  • Projections — defined projections and their storage.
  • Dependencies — upstream and downstream objects (views, dictionaries) that reference or are referenced by the table.
  • Table metadata — engine, total rows, compressed size.

All queries are read-only. No writes are issued.

Pages

PageRouteWhat it showsSystem tables
Data Explorer/explorerDatabase tree; table details: columns, DDL, indexes, projections, skip indexes, dependenciessystem.databases, system.tables, system.columns, system.projection_parts, system.data_skipping_indices, system.dictionaries

Permissions & access

The Data Explorer shares the tables feature id with all other table pages. Gating or disabling tables affects the explorer too:

## Gate to authenticated users
CHM_FEATURE_TABLES_ACCESS=authenticated

## Disable entirely
CHM_FEATURE_TABLES_ENABLED=false
## or
CHM_DISABLED_FEATURES=tables
## CHM_CONFIG_FILE (TOML)
[features.tables]
access = "authenticated"

Configuration

No feature-specific configuration. Global query timeout applies:

CLICKHOUSE_MAX_EXECUTION_TIME=60

Notes & limitations

  • system.data_skipping_indices — available since ClickHouse 20.6. The skip-index panel is hidden on older versions.
  • system.projection_parts — projections were introduced in ClickHouse 21.6. The projections panel is hidden on older versions.
  • Dependencies — dependency tracking uses the dependencies_database and dependencies_table arrays in system.tables. These arrays are populated for materialized views and dictionaries. Direct table references in ad-hoc queries are not tracked.
  • The explorer is read-only. You cannot create, alter, or drop objects from this page.
  • On clusters with many databases (hundreds), the initial database list query against system.databases may be slow. Increase CLICKHOUSE_MAX_EXECUTION_TIME if needed.