docs-v2/content/influxdb/cloud-dedicated/admin/query-system-data.md

---
title: Query system data
description: >
  Query system tables in your InfluxDB Cloud Dedicated cluster to see data related
  to queries, tables, partitions, and compaction in your cluster.
menu:
  influxdb_cloud_dedicated:
    parent: Administer InfluxDB Cloud
    name: Query system data
weight: 105
related:
  - /influxdb/cloud-dedicated/reference/cli/influxctl/query/
---

{{< product-name >}} stores data related to queries, tables, partitions, and
compaction in system tables in your cluster.
Query data in your cluster's system tables for information about your cluster.

- [Query system tables](#query-system-tables)
- [System tables](#system-tables)
- [System query examples](#system-query-examples)

{{% warn %}}
#### May impact overall cluster performance

Querying InfluxDB v3 system tables may impact the overall write and query
performance of your {{< product-name omit=" Clustered" >}} cluster.

<!--------------- UPDATE THE DATE BELOW AS EXAMPLES ARE UPDATED --------------->

#### System tables are subject to change

System tables are not part of InfluxDB's stable API and may change with new releases.
The provided schema information and query examples are valid as of **August 22, 2024**.
If you detect a schema change or a non-functioning query example, please
[submit an issue](https://github.com/influxdata/docs-v2/issues/new/choose).

<!--------------- UPDATE THE DATE ABOVE AS EXAMPLES ARE UPDATED --------------->
{{% /warn %}}

## Query system tables

{{% warn %}}
_Querying system tables [may impact overall cluster performance](#may-impact-overall-cluster-performance)._
{{% /warn %}}

{{% note %}}
Querying system tables with `influxctl` requires **`influxctl` v2.8.0 or newer**.
{{% /note %}}

Use the [`influxctl query` command](/influxdb/cloud-dedicated/reference/cli/influxctl/query/)
and SQL to query system tables. Provide the following:

- **Enable system tables** with the `--enable-system-tables` command flag.
- **Database token**: A [database token](/influxdb/cloud-dedicated/admin/tokens/#database-tokens)
  with read permissions on the specified database. Uses the `token` setting from
  the [`influxctl` connection profile](/influxdb/cloud-dedicated/reference/cli/influxctl/#configure-connection-profiles)
  or the `--token` command flag.
- **Database name**: The name of the database to query information about.
  Uses the `database` setting from the
  [`influxctl` connection profile](/influxdb/cloud-dedicated/reference/cli/influxctl/#configure-connection-profiles)
  or the `--database` command flag.
- **SQL query**: The SQL query to execute.
  Pass the query in one of the following ways:

  - a string on the command line
  - a path to a file that contains the query
  - a single dash (`-`) to read the query from stdin

{{% code-placeholders "DATABASE_(TOKEN|NAME)|SQL_QUERY" %}}

{{< code-tabs-wrapper >}}
{{% code-tabs %}}
[string](#)
[file](#)
[stdin](#)
{{% /code-tabs %}}
{{% code-tab-content %}}
```sh
influxctl query \
  --enable-system-tables \
  --database DATABASE_NAME \
  --token DATABASE_TOKEN \
  "SQL_QUERY"
```
{{% /code-tab-content %}}
{{% code-tab-content %}}
```sh
influxctl query \
  --enable-system-tables \
  --database DATABASE_NAME \
  --token DATABASE_TOKEN \
  /path/to/query.sql
```
{{% /code-tab-content %}}
{{% code-tab-content %}}
```sh
cat ./query.sql | influxctl query \
  --enable-system-tables \
  --database DATABASE_NAME \
  --token DATABASE_TOKEN \
  - 
```
{{% /code-tab-content %}}
{{< /code-tabs-wrapper >}}

{{% /code-placeholders %}}

Replace the following:

- {{% code-placeholder-key %}}`DATABASE_TOKEN`{{% /code-placeholder-key %}}:
  A database token with read access to the specified database
- {{% code-placeholder-key %}}`DATABASE_NAME`{{% /code-placeholder-key %}}:
  The name of the database to query information about.
- {{% code-placeholder-key %}}`SQL_QUERY`{{% /code-placeholder-key %}}:
  The SQL query to execute. For examples, see
  [System query examples](#system-query-examples).

When prompted, enter `y` to acknowledge the potential impact querying system
tables may have on your cluster.

## System tables

{{% warn %}}
_System tables are [subject to change](#system-tables-are-subject-to-change)._
{{% /warn %}}

- [system.queries](#systemqueries)
- [system.tables](#systemtables)
- [system.partitions](#systempartitions)
- [system.compactor](#systemcompactor)

### system.queries

The `system.queries` table contains an unpersisted log of queries run against
the current [InfluxDB Querier](/influxdb/cloud-dedicated/reference/internals/storage-engine/#querier)
to which your query is routed.
The query log is specific to the current Querier and is not shared across Queriers
in your cluster.
Logs are scoped to the specified database.

{{< expand-wrapper >}}
{{% expand "View `system.queries` schema" %}}

The `system.queries` table contains the following columns:

- id
- phase
- issue_time
- query_type
- query_text  
- partitions
- parquet_files
- plan_duration
- permit_duration
- execute_duration
- end2end_duration
- compute_duration
- max_memory
- success
- running
- cancelled
- trace_id

{{% /expand %}}
{{< /expand-wrapper >}}

### system.tables

The `system.tables` table contains information about tables in the specified database.

{{< expand-wrapper >}}
{{% expand "View `system.tables` schema" %}}

The `system.tables` table contains the following columns:

- table_name
- partition_template

{{% /expand %}}
{{< /expand-wrapper >}}

### system.partitions

The `system.partitions` table contains information about partitions associated
with the specified database.

{{< expand-wrapper >}}
{{% expand "View `system.partitions` schema" %}}

The `system.partitions` table contains the following columns:

- partition_id
- table_name
- partition_key
- last_new_file_created_at
- num_files
- total_size_mb

{{% /expand %}}
{{< /expand-wrapper >}}

### system.compactor

The `system.compaction` table contains information about compacted partition Parquet
files associated with the specified database.

{{< expand-wrapper >}}
{{% expand "View `system.compactor` schema" %}}

The `system.compactor` table contains the following columns:

- partition_id
- table_name 
- partition_key
- total_l0_files
- total_l1_files
- total_l2_files
- total_l0_bytes
- total_l1_bytes
- total_l2_bytes
- skipped_reason

{{% /expand %}}
{{< /expand-wrapper >}}

## System query examples

- [Query logs](#query-logs)
  - [View all stored query logs](#view-all-stored-query-logs)
  - [View query logs for queries with end-to-end durations above a threshold](#view-query-logs-for-queries-with-end-to-end-durations-above-a-threshold)
- [Partitions](#partitions)
  - [View partition templates of all tables](#view-partition-templates-of-all-tables)
  - [View the partition template of a specific table](#view-the-partition-template-of-a-specific-table)
  - [View all partitions for a table](#view-all-partitions-for-a-table)
  - [View the number of partitions per table](#view-the-number-of-partitions-per-table)
  - [View the number of partitions for a specific table](#view-the-number-of-partitions-for-a-specific-table)
- [Storage usage](#storage-usage)
  - [View the size of tables in megabytes](#view-the-size-of-tables-in-megabytes)
  - [View the size of a specific table in megabytes](#view-the-size-of-a-specific-table-in-megabytes)
  - [View the total size of all compacted partitions per table in bytes](#view-the-total-size-of-all-compacted-partitions-per-table-in-bytes)
  - [View the total size of all compacted partitions in bytes](#view-the-total-size-of-all-compacted-partitions-in-bytes)
- [Compaction](#compaction)
  - [View overall compaction totals for each table](#view-overall-compaction-totals-for-each-table)
  - [View overall compaction totals for a specific table](#view-overall-compaction-totals-for-a-specific-table)

In the examples below, replace {{% code-placeholder-key %}}`TABLE_NAME`{{% /code-placeholder-key %}}
with the name of the table you want to query information about.

--- 

{{% code-placeholders "TABLE_NAME" %}}

### Query logs

#### View all stored query logs

```sql
SELECT * FROM system.queries
```

#### View query logs for queries with end-to-end durations above a threshold

The following returns query logs for queries with an end-to-end duration greater
than 50 milliseconds.

```sql
SELECT * FROM system.queries WHERE end2end_duration::BIGINT > (50 * 1000000)
```

---

### Partitions

#### View partition templates of all tables

```sql
SELECT * FROM system.tables
```

#### View the partition template of a specific table

```sql
SELECT * FROM system.tables WHERE table_name = 'TABLE_NAME'
```

#### View all partitions for a table

```sql
SELECT * FROM system.partitions WHERE table_name = 'TABLE_NAME'
```

#### View the number of partitions per table

```sql
SELECT
  table_name,
  COUNT(*) AS partition_count
FROM
  system.partitions
GROUP BY
  table_name
```

#### View the number of partitions for a specific table

```sql
SELECT
  COUNT(*) AS partition_count
FROM
  system.partitions
WHERE
  table_name = 'TABLE_NAME'
```

---

### Storage usage

#### View the size of tables in megabytes

```sql
SELECT
  table_name,
  SUM(total_size_mb) AS total_size_mb
FROM
  system.partitions
GROUP BY
  table_name
```

#### View the size of a specific table in megabytes

```sql
SELECT
  SUM(total_size_mb) AS total_size_mb
FROM
  system.partitions
WHERE
  table_name = 'TABLE_NAME'
```

#### View the total size of all compacted partitions per table in bytes

```sql
SELECT
  table_name,
  SUM(total_l0_bytes) + SUM(total_l1_bytes) + SUM(total_l2_bytes) AS total_bytes
FROM
  system.compactor
GROUP BY
  table_name
```

#### View the total size of all compacted partitions in bytes

```sql
SELECT
  SUM(total_l0_bytes) + SUM(total_l1_bytes) + SUM(total_l2_bytes) AS total_bytes
FROM
  system.compactor
```

---

### Compaction

#### View overall compaction totals for each table

```sql
SELECT
  table_name,
  SUM(total_l0_files) AS total_l0_files,
  SUM(total_l1_files) AS total_l1_files,
  SUM(total_l2_files) AS total_l2_files,
  SUM(total_l0_bytes) AS total_l0_bytes,
  SUM(total_l1_bytes) AS total_l1_bytes,
  SUM(total_l2_bytes) AS total_l2_bytes
FROM
  system.compactor
GROUP BY
  table_name
```

#### View overall compaction totals for a specific table

```sql
SELECT
  SUM(total_l0_files) AS total_l0_files,
  SUM(total_l1_files) AS total_l1_files,
  SUM(total_l2_files) AS total_l2_files,
  SUM(total_l0_bytes) AS total_l0_bytes,
  SUM(total_l1_bytes) AS total_l1_bytes,
  SUM(total_l2_bytes) AS total_l2_bytes
FROM
  system.compactor
WHERE
  table_name = 'TABLE_NAME'
```

{{% /code-placeholders %}}