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Tablestore:Naming conventions and data types

Last Updated:May 09, 2025

This topic describes the naming conventions for tables and columns, as well as the data types supported by primary key columns and attribute columns.

Naming conventions

The following table describes the naming conventions for tables and columns.

Item

Description

Element

A name consists of uppercase letters (A to Z) or lowercase letters (a to z), digits (0 to 9), and underscores (_).

First letter of a name

A name must start with an uppercase letter (A to Z), a lowercase letter (a to z), or an underscore (_).

Case sensitivity

A name is case-sensitive.

Length

A name can be 1 to 255 characters in length.

Uniqueness

  • A table name must be unique in the same instance.

  • Table names can be the same in different instances.

Data types

Data types supported by primary key columns include STRING, INTEGER, and BINARY. Data types supported by attribute columns include STRING, INTEGER, DOUBLE, BOOLEAN, and BINARY.

  • Data types supported by primary key columns

    Data type

    Definition

    Size

    String

    Data is UTF-8 encoded.

    Up to 1 KB

    Integer

    Data is 64-bit signed integers. Auto-increment primary key columns are supported.

    8 bytes

    Binary

    Data is of the BINARY type.

    Up to 1 KB

  • Data types supported by attribute columns

    Data type

    Definition

    Size

    String

    Data is UTF-8 encoded. Empty strings are allowed.

    For more information, see Limits on the Wide Column model.

    Integer

    Data is 64-bit signed integers.

    8 bytes

    Double

    Data is 64-bit and of the DOUBLE type.

    8 bytes

    Boolean

    Data is of the BOOLEAN type. The value can be True or False.

    1 byte

    Binary

    Data is of the BINARY type. Empty values are allowed.

    For more information, see Limits on the Wide Column model.

References

Data types