MatrixOne Catalog

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
host	0.0.0.0
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
…