Note
- In V4.3.x, this view is available starting with V4.3.2.
- In V4.2.x, this view is available starting with V4.2.3.
Purpose
The V$OB_COMPATIBILITY_CONTROL view displays all the features that can be controlled for compatibility with different OceanBase Database releases.
Applicability
This view is applicable only to OceanBase Database in MySQL mode.
Columns
Column |
Type |
Nullable? |
Description |
|---|---|---|---|
| NAME | varchar(128) | NO | The name of the feature. |
| DESCRIPTION | varchar(4096) | NO | The description of the feature. |
| IS_ENABLE | varchar(5) | NO | Indicates whether the feature is enabled. |
| ENABLE_VERSIONS | longtext | NO | The range of versions for which the feature is enabled. It is represented as a series of intervals. For example: [4.2.3.1, 4.3.0.0), [4.3.1.0, +∞) |
Sample query
In the sys tenant, query all the features that can be controlled for compatibility with different OceanBase Database releases.
obclient [oceanbase]> SELECT * FROM oceanbase.V$OB_COMPATIBILITY_CONTROL;
The query result is as follows:
+-------------------+---------------------------------------------------------------------------------------+-----------+---------------------------------+
| NAME | DESCRIPTION | IS_ENABLE | ENABLE_VERSIONS |
+-------------------+---------------------------------------------------------------------------------------+-----------+---------------------------------+
| FUNC_REPLACE_NULL | The result of REPLACE('abd', '', null) is different in MySQL 5.7 and 8.0 | TRUE | [4.2.3.0, 4.3.0.0), [4.3.2.0, ) |
| UPD_LIMIT_OFFSET | MySQL do not support the use of OFFSET in the LIMIT clause of UPDATE/DELETE statement | TRUE | [4.2.3.0, 4.3.0.0), [4.3.2.0, ) |
| PROJECT_NULL | MySQL will rename the projection item names with pure null values to `NULL` | TRUE | [4.2.3.0, 4.3.0.0), [4.3.2.0, ) |
| VAR_NAME_LENGTH | MySQL will limit the length of user-defined variable names to within 64 characters | TRUE | [4.2.3.0, 4.3.0.0), [4.3.2.0, ) |
+-------------------+---------------------------------------------------------------------------------------+-----------+---------------------------------+
4 rows in set (0.012 sec)