[#MDEV-26775] Error messages about unavailable compression libraries not returned in diagnostics

As we are knowingly introducing possible upgrade difficulty in 10.7 by disabling by default compression libraries which were previously enabled, it is important to at least simplify problem handling for users who encounter it.

It appears that the server/InnoDB is quite capable of discovering what exactly is missing. When a table compressed with an uninstalled algorithm is queried, a detailed error message is written to the error log:

2021-10-06 20:05:31 4 [ERROR] InnoDB: Table `test`.`t` is compressed with snappy, which is not currently loaded. Please load the snappy provider plugin to open the table

But in the response to SQL, a user can only see ER_NO_SUCH_TABLE_IN_ENGINE:

preview-10.7-MDEV-12933-provider-plugins 67a8fca9b7
MariaDB [test]> select * from t;
ERROR 1932 (42S02): Table 'test.t' doesn't exist in engine
MariaDB [test]> show warnings;
+-------+------+----------------------------------------+
\| Level \| Code \| Message \|
+-------+------+----------------------------------------+
\| Error \| 1932 \| Table 'test.t' doesn't exist in engine \|
+-------+------+----------------------------------------+
1 row in set (0.000 sec)

Consequently, the same non-informative diagnostics is produced by mysql_upgrade:

Phase 6/7: Checking and upgrading tables

Processing databases

information_schema

performance_schema

sys

sys.sys_config                                     OK

test

test.t

Error    : Table 'test.t' doesn't exist in engine

status   : Operation failed

tmp

Repairing tables

test.t

Error    : Table 'test.t' doesn't exist in engine

status   : Operation failed

Phase 7/7: Running 'FLUSH PRIVILEGES'

OK

It would be great if the missing algorithm was indicated in the error messages returned to clients.

[MDEV-26775] Error messages about unavailable compression libraries not returned in diagnostics Created: 2021-10-06 Updated: 2023-11-28
Status:	Open
Project:	MariaDB Server
Component/s:	Plugins
Affects Version/s:	N/A
Fix Version/s:	10.11

[MDEV-26775] Error messages about unavailable compression libraries not returned in diagnostics Created: 2021-10-06 Updated: 2023-11-28