maxscale key limitations?
we have been using mariaDB for a number of years for a project. we want to start using mariaDB in a galera cluster, and use maxscale/cdc-client to trigger when changes have been made to mariaDB. We basically have a single table stored in mariaDB, and its key is a 16 byte hex value. by this I mean it is a 16 byte character array, with each element of the array comprising two hexadecimal digits. The non-key element of a tuple is just a variable length string. We've used this table in mariaDB for quite a few years without any issues. Here's an example of the table definition:
<TableDef name = "NF_PROFILE_JSON" repl = "yes"> <ColumnDef name = "nfinstanceid" primary-key = "yes"> <ColumnDomain domain = "DMUCHAR" length="16"/> </ColumnDef> <ColumnDef name = "nfprofile"> <ColumnDomain domain = "DMTEXT"/> </ColumnDef> </TableDef>
But now, the issue we are having is when we insert a tuple into this mariaDB table, maxscale complains:
2024-04-03 19:34:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1609339, record number 2. 2024-04-03 19:44:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1614292, record number 2. 2024-04-03 19:44:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1619917, record number 2. 2024-04-03 19:54:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1624870, record number 2. 2024-04-03 19:54:15 error : Failed to read field value 'nfinstanceid', type 'unknown type' at file offset 1630495, record number 2.
There are far more entries than this, this is just a sample.
Seems maxscale cannot handle 16 byte hex keys? If I insert into mariadb with a short length hex key, there is no issue. So instead of inserting a 16 byte hex key, if I insert X'111111, for example, this works just fine.
Is there any workaround for this?
Answer Answered by Markus Mäkelä in this comment.
Would it be possible for you to open a bug report for this in the MariaDB Jira under the MaxScale project? Here's the link to the Jira project: https://jira.mariadb.org/browse/MXS
If you can, please include the output of SHOW_CREATE_TABLE_NF_PROFILE_JSON
so that we'll know what the actual column type is. If you can also include some dummy data and the MaxScale version this affects, it'd make fixing it much easier.