Updated on 2024-05-07 GMT+08:00

ADM_TAB_COLUMNS

ADM_TAB_COLUMNS displays information about the columns of tables and views. Each column of each table and view in the database has a row of data in ADM_TAB_COLUMNS. By default, only the system administrator can access this view. Common users can access the view only after being authorized. This view exists in both PG_CATALOG and SYS schema.

Table 1 ADM_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 a 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 a 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 is set to 0 for other data types.

nullable

bpchar

Specifies whether the column can be null.

  • y: yes.
  • n: no. For primary key constraints and non-null constraints, the value is n.

column_id

integer

Sequence number of a column when a table is created.

default_length

numeric

Length of the default value of a column, in bytes. This column is left blank if no default value left.

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

timestamp(0) without time zone

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

Column length (in bytes) which 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.

  • 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.