docs-v2/content/shared/v3-distributed-admin-custom-partitions/define-custom-partitions.md

Use the influxctl CLI to define custom partition strategies when creating a database or table. By default, {{< product-name >}} partitions data by day.

The partitioning strategy of a database or table is determined by a partition template which defines the naming pattern for partition keys. Partition keys uniquely identify each partition. When a partition template is applied to a database, it becomes the default template for all tables in that database, but can be overridden when creating a table.

• Create a database with a custom partition template
• Create a table with a custom partition template
• Example partition templates

{{% warn %}}

Partition templates can only be applied on create

You can only apply a partition template when creating a database or table. You can't update a partition template on an existing resource. {{% /warn %}}

Use the following command flags to identify partition template parts:

• --template-tag: An InfluxDB tag to use in the partition template.
• --template-tag-bucket: An InfluxDB tag and number of "buckets" to group tag values into. Provide the tag key and the number of buckets to bucket tag values into separated by a comma: tagKey,N.
• --template-timeformat: A Rust strftime date and time string that specifies the time format in the partition template and determines the time interval to partition by.

{{% note %}} A partition template can include up to 7 total tag and tag bucket parts and only 1 time part. {{% /note %}}

View partition template part restrictions.

{{% note %}}

Always provide a time format when using custom partitioning

When defining a custom partition template for your database or table using any of the influxctl --template-* flags, always include the --template-timeformat flag with a time format to use in your partition template. Otherwise, InfluxDB omits time from the partition template and won't compact partitions. {{% /note %}}

Create a database with a custom partition template

The following example creates a new example-db database and applies a partition template that partitions by distinct values of two tags (room and sensor-type), bucketed values of the customerID tag, and by day using the time format %Y-%m-%d:

influxctl database create \
  --template-tag room \
  --template-tag sensor-type \
  --template-tag-bucket customerID,500 \
  --template-timeformat '%Y-%m-%d' \
  example-db

Create a table with a custom partition template

The following example creates a new example-table table in the specified database and applies a partition template that partitions by distinct values of two tags (room and sensor-type), bucketed values of the customerID tag, and by month using the time format %Y-%m:

{{% code-placeholders "DATABASE_NAME" %}}

influxctl table create \
  --template-tag room \
  --template-tag sensor-type \
  --template-tag-bucket customerID,500 \
  --template-timeformat '%Y-%m' \
  DATABASE_NAME \
  example-table

{{% /code-placeholders %}}

Replace the following in your command:

• {{% code-placeholder-key %}}DATABASE_NAME{{% /code-placeholder-key %}}: your {{% product-name %}} database

Example partition templates

Given the following line protocol with a 2024-01-01T00:00:00Z timestamp:

prod,line=A,station=weld1 temp=81.9,qty=36i 1704067200000000000

Partitioning by distinct tag values

Description	Tag parts	Time part	Resulting partition key
By day (default)		%Y-%m-%d	2024-01-01
By month		%Y-%m	2024-01
By year		%Y	2024
Single tag, by day	line	%Y-%m-%d	A | 2024-01-01
Single tag, by month	line	%Y-%m	A | 2024-01
Single tag, by year	line	%Y	A | 2024
Multiple tags, by day	line, station	%Y-%m-%d	A | weld1 | 2024-01-01
Multiple tags, by month	line, station	%Y-%m	A | weld1 | 2024-01
Multiple tags, by year	line, station	%Y	A | weld1 | 2024

Partition by tag buckets

Description	Tag part	Tag bucket part	Time part	Resulting partition key
Distinct tag, tag buckets, by day	line	station,100	%Y-%m-%d	A | 3 | 2024-01-01
Distinct tag, tag buckets, by month	line	station,500	%Y-%m	A | 303 | 2024-01