Creates a TimescaleDB hypertable from a PostgreSQL table (replacing the latter), partitioned on time and with the option to partition on one or more other columns. The PostgreSQL table cannot be an already partitioned table (declarative partitioning or inheritance). In case of a non-empty table, it is possible to migrate the data during hypertable creation using the migrate_data option, although this might take a long time and has certain limitations when the table contains foreign key constraints (see below).

After creation, all actions, such as ALTER TABLE, SELECT, etc., still work on the resulting hypertable.

For more information about using hypertables, including chunk size partitioning, see the hypertable section.

relationREGCLASSIdentifier of table to convert to hypertable.
time_column_nameREGCLASSName of the column containing time values as well as the primary column to partition by.
partitioning_columnREGCLASSName of an additional column to partition by. If provided, the number_partitions argument must also be provided.
number_partitionsINTEGERNumber of hash partitions to use for partitioning_column. Must be > 0.
chunk_time_intervalINTERVALEvent time that each chunk covers. Must be > 0. Default is 7 days.
create_default_indexesBOOLEANWhether to create default indexes on time/partitioning columns. Default is TRUE.
if_not_existsBOOLEANWhether to print warning if table already converted to hypertable or raise exception. Default is FALSE.
partitioning_funcREGCLASSThe function to use for calculating a value's partition.
associated_schema_nameREGCLASSName of the schema for internal hypertable tables. Default is _timescaledb_internal.
associated_table_prefixTEXTPrefix for internal hypertable chunk names. Default is _hyper.
migrate_dataBOOLEANSet to TRUE to migrate any existing data from the relation table to chunks in the new hypertable. A non-empty table generates an error without this option. Large tables may take significant time to migrate. Defaults to FALSE.
time_partitioning_funcREGCLASSFunction to convert incompatible primary time column values to compatible ones. The function must be IMMUTABLE.
replication_factorINTEGERReplication factor to use with distributed hypertable. If not provided, value is determined by the timescaledb.hypertable_replication_factor_default GUC.
data_nodesARRAYThis is the set of data nodes that are used for this table if it is distributed. This has no impact on non-distributed hypertables. If no data nodes are specified, a distributed hypertable uses all data nodes known by this instance.
distributedBOOLEANSet to TRUE to create distributed hypertable. If not provided, value is determined by the timescaledb.hypertable_distributed_default GUC. When creating a distributed hypertable, consider using create_distributed_hypertable in place of create_hypertable. Default is NULL.
hypertable_idINTEGERID of the hypertable in TimescaleDB.
schema_nameTEXTSchema name of the table converted to hypertable.
table_nameTEXTTable name of the table converted to hypertable.
createdBOOLEANTRUE if the hypertable was created, FALSE when if_not_exists is true and no hypertable was created.

If you use SELECT * FROM create_hypertable(...) you get the return value formatted as a table with column headings.

The use of the migrate_data argument to convert a non-empty table can lock the table for a significant amount of time, depending on how much data is in the table. It can also run into deadlock if foreign key constraints exist to other tables.

When converting a normal SQL table to a hypertable, pay attention to how you handle constraints. A hypertable can contain foreign keys to normal SQL table columns, but the reverse is not allowed. UNIQUE and PRIMARY constraints must include the partitioning key.

The deadlock is likely to happen when concurrent transactions simultaneously try to insert data into tables that are referenced in the foreign key constraints and into the converting table itself. The deadlock can be prevented by manually obtaining SHARE ROW EXCLUSIVE lock on the referenced tables before calling create_hypertable in the same transaction, see PostgreSQL documentation for the syntax.

The time column supports the following data types:


The type flexibility of the 'time' column allows the use of non-time-based values as the primary chunk partitioning column, as long as those values can increment.

For incompatible data types (for example, jsonb) you can specify a function to the time_partitioning_func argument which can extract a compatible data type.

The units of chunk_time_interval should be set as follows:

  • For time columns having timestamp or DATE types, the chunk_time_interval should be specified either as an interval type or an integral value in microseconds.
  • For integer types, the chunk_time_interval must be set explicitly, as the database does not otherwise understand the semantics of what each integer value represents (a second, millisecond, nanosecond, etc.). So if your time column is the number of milliseconds since the UNIX epoch, and you wish to have each chunk cover 1 day, you should specify chunk_time_interval => 86400000.

In case of hash partitioning (in other words, if number_partitions is greater than zero), it is possible to optionally specify a custom partitioning function. If no custom partitioning function is specified, the default partitioning function is used. The default partitioning function calls PostgreSQL's internal hash function for the given type, if one exists. Thus, a custom partitioning function can be used for value types that do not have a native PostgreSQL hash function. A partitioning function should take a single anyelement type argument and return a positive integer hash value. Note that this hash value is not a partition ID, but rather the inserted value's position in the dimension's key space, which is then divided across the partitions.


The time column in create_hypertable must be defined as NOT NULL. If this is not already specified on table creation, create_hypertable automatically adds this constraint on the table when it is executed.

Convert table conditions to hypertable with just time partitioning on column time:

SELECT create_hypertable('conditions', 'time');

Convert table conditions to hypertable, setting chunk_time_interval to 24 hours.

SELECT create_hypertable('conditions', 'time', chunk_time_interval => 86400000000);
SELECT create_hypertable('conditions', 'time', chunk_time_interval => INTERVAL '1 day');

Convert table conditions to hypertable. Do not raise a warning if conditions is already a hypertable:

SELECT create_hypertable('conditions', 'time', if_not_exists => TRUE);

Time partition table measurements on a composite column type report using a time partitioning function. Requires an immutable function that can convert the column value into a supported column value:

CREATE TYPE report AS (reported timestamp with time zone, contents jsonb);
CREATE FUNCTION report_reported(report)
RETURNS timestamptz
'SELECT $1.reported';
SELECT create_hypertable('measurements', 'report', time_partitioning_func => 'report_reported');

Time partition table events, on a column type jsonb (event), which has a top level key (started) containing an ISO 8601 formatted timestamp:

CREATE FUNCTION event_started(jsonb)
RETURNS timestamptz
$func$SELECT ($1->>'started')::timestamptz$func$;
SELECT create_hypertable('events', 'event', time_partitioning_func => 'event_started');


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