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Object Naming Convention
Learn the object naming convention in TiDB.

Object Naming Convention

This document introduces the rules to name database objects, such as database, table, index, and user.

General rules

  • It is recommended to use meaningful English words separated by underscores.
  • Use only letters, numbers, and underscores in a name.
  • Avoid using TiDB reserved words, such as group and order, as column names.
  • It is recommended to use lowercase letters for all database objects.

Database naming convention

It is recommended to differentiate database names by business, product, or other metrics and use no more than 20 characters in a database name. For example, you can name a temporary library as tmp_crm or a test library as test_crm.

Table naming convention

  • Use the same prefix for tables of the same business or module, and make sure that the table name is self-explanatory as much as possible.
  • Separate words in a name by underscores. It is recommended to use no more than 32 characters in a table name.
  • It is recommended to annotate the purpose of the table for a better understanding. For example:
    • Temporary table: tmp_t_crm_relation_0425
    • Backup table: bak_t_crm_relation_20170425
    • Temporary table of business operations: tmp_st_{business code}_{creator abbreviation}_{date}
    • Record table of accounts period: t_crm_ec_record_YYYY{MM}{dd}
  • Create separate databases for tables of different business modules and add annotations accordingly.

Column naming convention

  • The column naming is the actual meaning or abbreviation of the column.
  • It is recommended to use the same column name between tables with the same meaning.
  • It is recommended to add annotations to columns and specify named values for enumerated types, such as "0: offline, 1: online".
  • It is recommended to name the boolean column as is_{description}. For example, the column of a member table that indicates whether the member is enabled, can be named as is_enabled.
  • It is not recommended to name a column with more than 30 characters, and the number of columns should be less than 60.
  • Avoid using TiDB reserved words as column names, such as order, from, and desc. To check whether a keyword is reserved, see TiDB keywords.

Index naming convention

  • Primary key index: pk_{table_name_abbreviation}_{field_name_abbreviation}
  • Unique index: uk_{table_name_abbreviation}_{field_name_abbreviation}
  • Common index: idx_{table_name_abbreviation}_{field_name_abbreviation}
  • Column name with multiple words: use meaningful abbreviations