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MySQL NDB Cluster 8.0  /  ...  /  The ndbinfo dictionary_columns Table

6.16.22 The ndbinfo dictionary_columns Table

The table provides NDB dictionary information about columns of NDB tables. dictionary_columns has the columns listed here (with brief descriptions):

  • table_id

    ID of the table containing the column

  • column_id

    The column's unique ID

  • name

    Name of the column

  • column_type

    Data type of the column from the NDB API; see Column::Type, for possible values

  • default_value

    The column's default value, if any

  • nullable

    Either of NULL or NOT NULL

  • array_type

    The column's internal attribute storage format; one of FIXED, SHORT_VAR, or MEDIUM_VAR; for more information, see Column::ArrayType, in the NDB API documentation

  • storage_type

    Type of storage used by the table; either of MEMORY or DISK

  • primary_key

    1 if this is a primary key column, otherwise 0

  • partition_key

    1 if this is a partitioning key column, otherwise 0

  • dynamic

    1 if the column is dynamic, otherwise 0

  • auto_inc

    1 if this is an AUTO_INCREMENT column, otherwise 0

You can obtain information about all of the columns in a given table by joining dictionary_columns with the dictionary_tables table, like this:

SELECT dc.*
  FROM dictionary_columns dc
JOIN dictionary_tables dt
  ON dc.table_id=dt.table_id
WHERE dt.table_name='t1'
  AND dt.database_name='mydb';

The dictionary_columns table was added in NDB 8.0.29.

Note

Blob columns are not shown in this table. This is a known issue.