This patch removes restriction on creating a function with the same name
as the built-in function. The reason for lifting the restriction is to
avoid a name clash when introducing new built-in functions. The patch
also fixes some inconsistent behavior when creating or dropping a function
when the name specified is fully-qualified or not.
Refer to the below tables for more information.
Create function:
+---------+-------------+-------------------------+-------------------------------+-------------------------------+
| FQ Name | Built-in DB | Function Name | Existing Behavior | New Behavior |
+---------+-------------+-------------------------+-------------------------------+-------------------------------+
| Yes | Yes | Same as built-in | Same name exception | Cannot modify system database |
| Yes | Yes | Different than built-in | Cannot modify system database | Cannot modify system database |
| Yes | No | Same as built-in | Function created | Function created |
| Yes | No | Different than built-in | Function created | Function created |
| No | Yes | Same as built-in | Same name exception | Cannot modify system database |
| No | Yes | Different than built-in | Cannot modify system database | Cannot modify system database |
| No | No | Same as built-in | Same name exception | Function created |
| No | No | Different than built-in | Function created | Function created |
+---------+-------------+-------------------------+-------------------------------+-------------------------------+
Drop function:
+---------+-------------+-------------------------+-------------------------------+-------------------------------+
| FQ Name | Built-in DB | Function Name | Existing Behavior | New Behavior |
+---------+-------------+-------------------------+-------------------------------+-------------------------------+
| Yes | Yes | Same as built-in | Cannot modify system database | Cannot modify system database |
| Yes | Yes | Different than built-in | Cannot modify system database | Cannot modify system database |
| Yes | No | Same as built-in | Function dropped | Function dropped |
| Yes | No | Different than built-in | Function dropped | Function dropped |
| No | Yes | Same as built-in | Cannot modify system database | Cannot modify system database |
| No | Yes | Different than built-in | Cannot modify system database | Cannot modify system database |
| No | No | Same as built-in | Cannot modify system database | Function dropped |
| No | No | Different than built-in | Function dropped | Function dropped |
+---------+-------------+-------------------------+-------------------------------+-------------------------------+
Select function (no new behavior):
+---------+-------------+-------------------------+--------------------------------------------------------+
| FQ Name | Built-in DB | Function Name | Behavior |
+---------+-------------+-------------------------+--------------------------------------------------------+
| Yes | Yes | Same as built-in | Function in the specified database (built-in) executed |
| Yes | Yes | Different than built-in | Unknown function exception |
| Yes | No | Same as built-in | Function in the specified database executed |
| Yes | No | Different than built-in | Function in the specified database executed |
| No | Yes | Same as built-in | Built-in function executed |
| No | Yes | Different than built-in | Unknown function exception |
| No | No | Same as built-in | Built-in function executed |
| No | No | Different than built-in | Function in the current database executed |
+---------+-------------+-------------------------+--------------------------------------------------------+
Testing:
- Ran front-end tests
- Added end-to-end DDL function tests
Cherry-picks: not for 2.x
Change-Id: Ic30df56ac276970116715c14454a5a2477b185fa
Reviewed-on: http://gerrit.cloudera.org:8080/9800
Reviewed-by: Alex Behm <alex.behm@cloudera.com>
Tested-by: Impala Public Jenkins
08d386f0fc