CREATE TABLE

Basic syntax

Basic syntax:

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CREATE TABLE [IF NOT EXISTS]
    table_name ( column_definitions )
    [partition_options]
    ENGINE = engine_type
    [WITH ( table_options )];

Column definition syntax:

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column_name column_type [[NOT] NULL] [TAG | TIMESTAMP KEY | PRIMARY KEY] [DICTIONARY] [COMMENT '']

Partition options syntax:

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PARTITION BY KEY (column_list) [PARTITIONS num]

Table options syntax are key-value pairs. Value should be quoted with quotation marks ('). E.g.:

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... WITH ( enable_ttl='false' )

IF NOT EXISTS

Add IF NOT EXISTS to tell HoraeDB to ignore errors if the table name already exists.

Define Column

A column’s definition should at least contains the name and type parts. All supported types are listed here.

Column is default be nullable. i.e. NULL keyword is implied. Adding NOT NULL constrains to make it required.

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-- this definition
a_nullable int
-- equals to
a_nullable int NULL

-- add NOT NULL to make it required
b_not_null NOT NULL

A column can be marked as special column with related keyword.

For string tag column, we recommend to define it as dictionary to reduce memory consumption:

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`tag1` string TAG DICTIONARY

Engine

Specifies which engine this table belongs to. HoraeDB current support Analytic engine type. This attribute is immutable.

Partition Options

Note: This feature is only supported in distributed version.

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CREATE TABLE ... PARTITION BY KEY

Example below creates a table with 8 partitions, and partitioned by name:

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CREATE TABLE `demo` (
    `name` string TAG COMMENT 'client username',
    `value` double NOT NULL,
    `t` timestamp NOT NULL,
    timestamp KEY (t)
)
    PARTITION BY KEY(name) PARTITIONS 8
    ENGINE=Analytic
    with (
    enable_ttl='false'
)