Help Center/GaussDB/Developer Guide(Distributed_V2.0-3.x)/System Catalogs and System Views/System Views/MY_TAB_COLUMNS
Updated on 2025-08-19 GMT+08:00
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MY_TAB_COLUMNS

MY_TAB_COLUMNS displays the columns of the tables and views owned by the current user. This view exists in both PG_CATALOG and SYS schema. All users can access this view. Only the information about the user is displayed.

Table 1 MY_TAB_COLUMNS columns

Name

Type

Description

owner

character varying(64)

Table owner.

table_name

character varying(64)

Table name.

column_name

character varying(64)

Column name.

data_type

character varying(128)

Data type of the column.

data_type_mod

character varying(3)

Not supported. Its value is NULL.

data_type_owner

character varying(128)

Owner of the data type of a column.

data_length

integer

Length of the column, in bytes.

data_precision

integer

Precision of a data type. This column is valid for the numeric data type and NULL for other data types.

data_scale

integer

Number of decimal places. This column is valid for the numeric data type and 0 for other data types.

nullable

bpchar

Specifies whether a column can be empty (n for a primary key constraint or NOT NULL constraint).

column_id

integer

Sequence number of the column when the table is created.

default_length

numeric

Length of the default value of a column, in bytes.

data_default

text

Default value of a column.

num_distinct

numeric

Number of different values in a column.

low_value

raw

Minimum value in a column.

high_value

raw

Maximum value in a column.

density

numeric

Column density.

num_nulls

numeric

Number of empty values in a column.

num_buckets

numeric

Number of buckets in the histogram of a column.

last_analyzed

date

Last analysis date.

sample_size

numeric

Sample size used to analyze a column.

character_set_name

character varying(44)

Not supported. Its value is NULL.

char_col_decl_length

numeric

Declaration length of a column of the character type.

global_stats

character varying(3)

Not supported. Its value is NO.

user_stats

character varying(3)

Not supported. Its value is NO.

avg_col_len

numeric

Average length of a column, in bytes.

char_length

numeric

Length of a column, in characters. This parameter is valid only for the varchar, nvarchar2, bpchar, and char types.

char_used

character varying(1)

Not supported. Set it to B if the data type is varchar, nvarchar2, bpchar, or char, and to NULL for other data types.

v80_fmt_image

character varying(3)

Not supported. Its value is NULL.

data_upgraded

character varying(3)

Not supported. Its value is YES.

histogram

character varying(15)

Specifies whether the histogram exists and the type of the histogram if it exists.
  • NONE: no histogram.
  • FREQUENCY: frequency histogram.
  • EQUI_WIDTH: equal-width histogram.

default_on_null

character varying(3)

Not supported. Its value is NULL.

identity_column

character varying(3)

Not supported. Its value is NULL.

sensitive_column

character varying(3)

Not supported. Its value is NULL.

evaluation_edition

character varying(128)

Not supported. Its value is NULL.

unusable_before

character varying(128)

Not supported. Its value is NULL.

unusable_beginning

character varying(128)

Not supported. Its value is NULL.

collation

character varying(100)

Collation rule of a column. This column conflicts with reserved keywords. Therefore, add the view name when calling this column.

comments

text

Comment of a column.

schema

character varying(64)

Name of the namespace to which the column belongs.

Parent topic:System Views