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MatrixOne Catalog

MatrixOne catalog is a component where MatrixOne stores system information. We can access the system information by mo_catalog database. The mo_catalog database is created by MatrixOne at initialization.

In 0.5.1, the mo_catalog is not fully implemented, users can check basic information about the their database and tables, but writing values into mo_catalog by users is not supported yet.

There are three tables in the mo_catalog database:

mo_database table

This table contains the database information.

  • table structure:
Attributes Type Primary key Description
datname varchar(256) Primary key database name
dat_catalog_name varchar(256) catalog name
dat_createsql varchar(4096) create sql
  • table initial rows:

At initialization, mo_database have some default rows in place.

datname dat_catalog_name dat_createsql
mo_catalog def hardcode
information_schema def create database if not exists information_schema
system_metrics def

mo_tables table

This table contains the information about the table, index, view etc.

  • table structure:
Attributes Type Primary key Description
relname varchar(256) PK Name of the table, index, view, etc.
reldatabase varchar(256) PK,FK The database that contains this relation. reference mo_database.datname
relpersistence char(1) p = permanent table, t = temporary table
relkind char(1) r = ordinary table, i = index, S = sequence, v = view, m = materialized view
rel_comment varchar(1024) comment
rel_createsql varchar(4096) create sql
  • table initial rows:

At initialization, mo_tables have some default rows in place.

relname reldatabase repersistence relkind rel_createsql rel_comment
mo_database mo_catalog 'p' 'r' tae hardcode databases
mo_tables mo_catalog 'p' 'r' tae hardcode tables
mo_columns mo_catalog 'p' 'r' tae hardcode columns
mo_global_variables mo_catalog 'p' 'r' create sql system variables
mo_user mo_catalog 'p' 'r' create sql user
schemata information_schema 'p' 'v' create sql schemas
tables information_schema 'p' 'v' create sql tables
columns information_schema 'p' 'v' create sql columns
key_column_usage information_schema 'p' 'v' create sql columns related to unique, primary key, or foreign key
views information_schema 'p' 'v' create sql views

mo_columns table

This table contains the information about the table attributes.

  • table structure:
Attributes Type Primary key Description
att_database varchar(256) PK database
att_relname varchar(256) PK,UK The table this column belongs to.(references mo_tables.relname)
attname varchar(256) PK The column name
atttyp int The data type of this column (zero for a dropped column).
attnum int UK The number of the column. Ordinary columns are numbered from 1 up.
att_length int bytes count for the type.
attnotnull tinyint(1) This represents a not-null constraint.
atthasdef tinyint(1) This column has a default expression or generation expression.
att_default varchar(1024) default expression
attisdropped tinyint(1) This column has been dropped and is no longer valid. A dropped column is still physically present in the table, but is ignored by the parser and so cannot be accessed via SQL.
att_constraint_type char(1) p = primary key constraint, n=no constraint
att_is_unsigned tinyint(1) unsigned or not
att_is_auto_increment tinyint auto increment or not
att_comment varchar(1024) comment
att_is_hidden tinyint(1) hidden or not
  • table initial rows:
att_database att_relname attname atttyp attnum attnotnull atthasdef att_default attisdropped att_constraint_type att_is_unsigned att_is_auto_increment att_comment att_is_hidden
mo_catalog mo_database datname varchar 0 1 0 '' 0 'p' 0 0 'database name' 0
mo_catalog mo_database dat_catalog_name varchar 1 1 0 '' 0 'p' 0 0 'catalog' 0
mo_catalog mo_database dat_createsql varchar 2 1
mo_catalog mo_tables relname varchar 0 1 'p'
mo_catalog mo_tables reldatabase varchar 1 1 'p'
mo_catalog mo_tables relpersistence char 2 1
mo_catalog mo_tables relkind char 3 1
mo_catalog mo_tables rel_createsql varchar 4 0
mo_catalog mo_tables rel_comment varchar 5 0
mo_catalog mo_columns att_database varchar 0 1
mo_catalog mo_columns att_relname varchar 1 1
mo_catalog mo_columns attname varchar 2 1
mo_catalog mo_columns atttyp int 3 1
mo_catalog mo_columns attnum int 4 1
mo_catalog mo_columns attnotnull tinyint 5 1
mo_catalog mo_columns atthasdef tinyint 6 1
mo_catalog mo_columns att_default varchar 7 0
mo_catalog mo_columns attisdropped tinyint 8 1
mo_catalog mo_columns att_constraint_type char 9 1
mo_catalog mo_columns att_is_unsigned tinyint 10 1
mo_catalog mo_columns att_is_auto_increment tinyint 11 1
mo_catalog mo_columns att_comment varchar 12 0
mo_catalog mo_columns att_is_hidden tinyint 13 1

mo_global_variables table

This table contains the information about the system variables.

  • table structure:
Attributes Type Primary key Description
gv_variable_name varchar(256) PK variable name
gv_variable_value varchar(1024) variable value
  • table initial rows:
gv_variable_name gv_variable_value
gv_variable_name gv_variable_value
max_allowed_packet 67108864
version_comment MatrixOne
port 6001
storePath ./store
batchSizeInLoadData 40000

mo_user table

This table contains the information of user accounts.

  • table structure:
Attributes Type Primary key Description
user_host varchar(256) PK user host
user_name varchar(256) PK user name
Select_priv char 'N','Y'
Insert_priv char 'N','Y'
Update_priv char 'N','Y'
Delete_priv char 'N','Y'
Create_priv char 'N','Y'
Drop_priv char 'N','Y'
Reload_priv char 'N','Y'
Shutdown_priv char 'N','Y'
Process_priv char 'N','Y'
File_priv char 'N','Y'
Grant_priv char 'N','Y'
References_priv char 'N','Y'
Index_priv char 'N','Y'
Alter_priv char 'N','Y'
Show_db_priv char 'N','Y'
Super_priv char 'N','Y'
Create_tmp_table_priv char 'N','Y'
Lock_tables_priv char 'N','Y'
Execute_priv char 'N','Y'
Repl_slave_priv char 'N','Y'
Repl_client_priv char 'N','Y'
Create_view_priv char 'N','Y'
Show_view_priv char 'N','Y'
Create_routine_priv char 'N','Y'
Alter_routine_priv char 'N','Y'
Create_user_priv char 'N','Y'
Event_priv char 'N','Y'
Trigger_priv char 'N','Y'
Create_tablespace_priv char 'N','Y'
max_questions int unsigned
max_updates int unsigned
max_connections int unsigned
max_user_connections int unsigned
authentication_string varchar(4096) password
account_locked char 'N','Y'
Create_role_priv char 'N','Y'
Drop_role_priv char 'N','Y'
  • table initial rows:
user_host user_name authentication_string
localhost root ''
localhost dump 111