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Create a hypertable

Hypertables are the core of TimescaleDB. Hypertables enable TimescaleDB to work efficiently with time-series data. Because TimescaleDB is PostgreSQL, all the regular PostgreSQL tables, indexes, stored procedures and other objects can be created alongside your TimescaleDB hypertables. This makes creating and working with TimescaleDB tables similar to regular PostgreSQL.

Hypertables and chunks

Hypertables and chunks make storing and querying times-series data fast at petabyte scale.

TimescaleDB automatically partitions time-series data into chunks, or sub-tables, based on time and space. You can configure chunk size so that recent chunks fit in memory for faster queries.

A hypertable is an abstraction layer over chunks that hold the time-series data. Hypertables enable you to query and access data from all the chunks within the hypertable. You get all the benefits of automatic chunking for time-series data, alongside the simplicity of working with what looks like a standard, single PostgreSQL table.

Hypertables and chunks enable superior performance for shallow and wide queries, like those used in real-time monitoring. They are also good for deep and narrow queries, like those used in time-series analysis.

For more information, see Hypertables and chunks.

Creating your first hypertable

  1. Create a regular PostgreSQL table to store the real-time stock trade data using CREATE TABLE:

    CREATE TABLE stocks_real_time (
      time TIMESTAMPTZ NOT NULL,
      symbol TEXT NOT NULL,
      price DOUBLE PRECISION NULL,
      day_volume INT NULL
    );
  2. Convert the regular table into a hypertable partitioned on the time column using the create_hypertable() function provided by TimescaleDB. You must provide the name of the table (stocks_real_time) and the column in that table that holds the timestamp data to use for partitioning (time):

    SELECT create_hypertable('stocks_real_time','time');
  3. Create an index to support efficient queries on the symbol and time columns:

    CREATE INDEX ix_symbol_time ON stocks_real_time (symbol, time DESC);

note

When you create a hypertable, it is automatically partitioned on the time column you provide as the second parameter to create_hypertable(). Also, TimescaleDB automatically creates an index on the time column. However, you'll often filter your time-series data on other columns as well. Using indexes appropriately helps your queries perform better.

Because you often query the stock trade data by the company symbol, you should add an index for it. Include the time column because time-series data typically looks for data in a specific period of time.

Create regular PostgreSQL tables for relational data

TimescaleDB isn't just for hypertables. Remember, TimescaleDB is PostgreSQL. When you have other relational data that enhances your time-series data, you can create regular PostgreSQL tables just as you would normally. For this dataset, there is one other table of data called company.

Creating regular PostgreSQL tables

  1. Add a table to store the company name and symbol for the stock trade data:

    CREATE TABLE company (
      symbol TEXT NOT NULL,
      name TEXT NOT NULL
    );
  2. You now have two tables within your TimescaleDB database. One hypertable named stocks_real_time, and one normal PostgreSQL table named company.

Next steps

Ingest some sample stock trade data into TimescaleDB. The next section, 'Add time-series data', shows you how to populate the tables you just created.

Learn more about hypertables and chunks

To learn more about hypertables and best practices for configuring chunks, see Hypertable How-To. For information about how hypertables help with storing and querying data, see the hypertables and chunks core concepts page.

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