ALL_TAB_COLUMNS

ALL_TAB_COLUMNS displays description of columns of the tables and views that the current user can access.

**Table 1** ALL_TAB_COLUMNS columns
Name	Type	Description
owner	character varying(64)	Owner of a table/view
table_name	character varying(64)	Table/View name
column_name	character varying(64)	Column name
data_type	character varying(128)	Data type of a column
column_id	integer	Column ID generated when an object is created or a column is added
data_length	integer	Length of the column, in bytes
avg_col_len	numeric	Average length of a column, in bytes
nullable	bpchar	Whether the column can be empty. For the primary key constraint and non-null constraint, the value is n.
data_precision	integer	Precision of the data type. This parameter is valid for the numeric data type and NULL for other types.
data_scale	integer	Number of decimal places. This parameter is valid for the numeric data type and 0 for other data types.
char_length	numeric	Length of a column, in characters. This parameter is valid only for the varchar, nvarchar2, bpchar, and char types.
schema	character varying(64)	Namespace that contains the table or view.
kind	text	Type of the current record. If the column belongs to a table, the value of this column is table. If the column belongs to a view, the value of this column is view.