Purpose
The DBA_TAB_COLS view displays all columns of all tables and views in the database.
This view differs from the DBA_TAB_COLUMNS view in that hidden columns are not filtered out.
Applicability
This topic applies only to OceanBase Database Enterprise Edition. OceanBase Database Community Edition provides only the MySQL mode.
Related views
ALL_TAB_COLSUSER_TAB_COLS
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| OWNER | VARCHAR2(128) | NO | The owner of the table or view. |
| TABLE_NAME | VARCHAR2(128) | NO | The name of the table or view. |
| COLUMN_NAME | VARCHAR2(128) | NO | The name of the column. |
| DATA_TYPE | VARCHAR2(128) | NO | The data type of the column. |
| DATA_TYPE_MOD | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| DATA_TYPE_OWNER | VARCHAR2(128) | NO | At present, this column is not supported and is NULL by default. |
| DATA_LENGTH | NUMBER | NO | The length of the column in bytes. |
| DATA_PRECISION | NUMBER | NO | The decimal precision for the NUMBER data type and the binary precision for the FLOAT data type. The value is NULL for all other data types. |
| DATA_SCALE | NUMBER | NO | The number of digits on the right of the decimal point in a number. |
| NULLABLE | VARCHAR2(1) | NO | Indicates whether the column can be null. |
| COLUMN_ID | NUMBER | NO | The sequence number of the column. |
| DEFAULT_LENGTH | NUMBER | NO | The default length of the column. |
| DATA_DEFAULT | VARCHAR2(128) | NO | The default value of the column. |
| NUM_DISTINCT | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| LOW_VALUE | VARCHAR2(128) | NO | At present, this column is not supported and is NULL by default. |
| HIGH_VALUE | VARCHAR2(128) | NO | At present, this column is not supported and is NULL by default. |
| DENSITY | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| NUM_NULLS | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| NUM_BUCKETS | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| LAST_ANALYZED | DATE | NO | At present, this column is not supported and is NULL by default. |
| SAMPLE_SIZE | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| CHARACTER_SET_NAME | VARCHAR2(44) | NO | At present, this column is not supported and is NULL by default. |
| CHAR_COL_DECL_LENGTH | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| GLOBAL_STATS | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| USER_STATS | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| AVG_COL_LEN | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| CHAR_LENGTH | NUMBER | NO | The character length of the column. |
| CHAR_USED | VARCHAR2(1) | NO | Indicates whether the column uses the byte length or the character length. |
| V80_FMT_IMAGE | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| DATA_UPGRADED | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| HIDDEN_COLUMN | VARCHAR2(3) | NO | Indicates whether the column is a hidden column. Valid values: |
| VIRTUAL_COLUMN | VARCHAR2(3) | NO | Indicates whether the column is a virtual column. Valid values: |
| SEGMENT_COLUMN_ID | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| INTERNAL_COLUMN_ID | NUMBER | NO | At present, this column is not supported and is NULL by default. |
| HISTOGRAM | VARCHAR2(15) | NO | At present, this column is not supported and is NULL by default. |
| QUALIFIED_COL_NAME | VARCHAR2(4000) | NO | The qualified column name. |
| DEFAULT_ON_NULL | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| IDENTITY_COLUMN | VARCHAR2(3) | NO | At present, this column is not supported and is NULL by default. |
| EVALUATION_EDITION | VARCHAR2(128) | NO | At present, this column is not supported and is NULL by default. |
| UNUSABLE_BEFORE | VARCHAR2(128) | NO | At present, this column is not supported and is NULL by default. |
| UNUSABLE_BEGINNING | VARCHAR2(128) | NO | At present, this column is not supported and is NULL by default. |
| COLLATION | VARCHAR2(100) | NO | At present, this column is not supported and is NULL by default. |
| COLLATED_COLUMN_ID | NUMBER | NO | At present, this column is not supported and is NULL by default. |