Purpose
This view displays the column information of table and view objects in all tenants.
Note
This view is introduced since OceanBase Database V4.0.0.
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| CON_ID | bigint(20) | NO | Tenant ID. |
| OWNER | varchar(128) | NO | The owner of the table, view, or cluster. |
| TABLE_NAME | varchar(128) | NO | The name of the table, view, or cluster. |
| COLUMN_NAME | varchar(128) | NO | The name of the column. |
| DATA_TYPE | varchar(128) | NO | The data type of the column. |
| DATA_TYPE_MOD | varchar(3) | NO | The data type modifier. Default value: NULL. |
| DATA_TYPE_OWNER | varchar(128) | NO | The owner of the data type. Default value: NULL. |
| DATA_LENGTH | bigint(21) | NO | The length of the column in bytes. |
| DATA_PRECISION | bigint(20) | NO | The number of digits to the right of the decimal point for the NUMBER data type; the binary precision for the FLOAT data type; and NULL for all other data types. |
| DATA_SCALE | bigint(20) | NO | The number of digits to the right of the decimal point in a number. |
| NULLABLE | varchar(1) | NO | Indicates whether the column allows NULL values. The value is YES if the column has a NOT NULL constraint or if the column is part of a PRIMARY KEY, or NO otherwise. |
| COLUMN_ID | bigint(20) | NO | The sequence number of the column. |
| DEFAULT_LENGTH | bigint(20) | NO | The length of the default value. |
| DATA_DEFAULT | mediumtext | NO | The default value of the column. |
| NUM_DISTINCT | bigint(20) | NO | The number of distinct values in the column. |
| LOW_VALUE | varchar(128) | NO | The minimum value in the column. |
| HIGH_VALUE | varchar(128) | NO | The maximum value in the column. |
| DENSITY | bigint(21) | NO | The selectivity of values that are less than 2 histogram endpoints in the histogram of the column. It does not represent the selectivity of values that are greater than or equal to 2 histogram endpoints. If the histogram is not available for the column, the value of this column is 1/ NUM_DISTINCT. |
| NUM_NULLS | bigint(20) | NO | The number of NULL values in the column. |
| NUM_BUCKETS | bigint(20) | NO | The number of buckets in the histogram of the column. |
| LAST_ANALYZED | date | NO | The date when the column was last analyzed. |
| SAMPLE_SIZE | bigint(20) | NO | The sample size used to analyze the column. |
| CHARACTER_SET_NAME | varchar(44) | NO | The character set name: CHAR_CSNCHAR_CS |
| CHAR_COL_DECL_LENGTH | bigint(0) | NO | The declared length of the column in characters. Default value: NULL |
| GLOBAL_STATS | varchar(3) | NO | YES if statistics are collected or incrementally maintained, or NO otherwise. |
| USER_STATS | varchar(3) | NO | YES if the statistics are directly input by users, or NO otherwise. |
| AVG_COL_LEN | bigint(21) | NO | The average length of the column in bytes. |
| CHAR_LENGTH | bigint(20) | NO | The length of the column in characters. This value applies only to the following data types: CHARVARCHAR2NCHARNVARCHAR2 |
| CHAR_USED | varchar(1) | NO | Indicates whether the column uses BYTE length semantics (B) or CHAR length semantics (C), or whether the data type is not any of the following: CHARVARCHAR2NCHARNVARCHAR2 |
| V80_FMT_IMAGE | varchar(3) | NO | The value is NULL by default. |
| DATA_UPGRADED | varchar(3) | NO | The value is NULL by default. |
| HIDDEN_COLUMN | varchar(3) | NO | YES if the column is a hidden column, or NO otherwise. |
| VIRTUAL_COLUMN | varchar(3) | NO | YES if the column is a virtual column, or NO otherwise. |
| SEGMENT_COLUMN_ID | bigint(0) | NO | The value is NULL by default. |
| INTERNAL_COLUMN_ID | bigint(0) | NO | The value is NULL by default. |
| HISTOGRAM | varchar(15) | NO | Indicates the presence or type of the histogram: NONEFREQUENCYTOP-FREQUENCYHEIGHT BALANCEDHYBRID |
| QUALIFIED_COL_NAME | text | NO | The qualified column name. |
| USER_GENERATED | varchar(3) | NO | The generation attribute of the column. Options:
NoteFor OceanBase Database V4.3.5, this column takes effect starting from V4.3.5 BP1. |
| DEFAULT_ON_NULL | varchar(3) | NO | The value is NULL by default. |
| IDENTITY_COLUMN | varchar(3) | NO | The value is NULL by default. |
| EVALUATION_EDITION | varchar(128) | NO | The value is NULL by default. |
| UNUSABLE_BEFORE | varchar(128) | NO | The value is NULL by default. |
| UNUSABLE_BEGINNING | varchar(128) | NO | The value is NULL by default. |
| COLLATION | varchar(100) | NO | The value is NULL by default. |
| COLLATED_COLUMN_ID | bigint(0) | NO | The value is NULL by default. |