I found a bug of MariaDB Connector for PowerBI.
I reported about it to PowerBI community, but they couldn't help it since they (MS) don't have the ownership of MariaDB Connector.
The following is my original post, so please refer to it and fix the problem.
I'm using PowerBI (version 2.92.706.0, 64-bit) and MariaDB as data source. I downloaded ODBC driver versions 3.1.11 from following link:
Connection & Simple import job worked well. But when I add text filtering (equality check) in Power Query Editor, it raises SQL syntax error like this:
[ma-3.1.11][10.3.25-MariaDB-0ubuntu0.20.04.1-log]You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'LONG VARCHAR) = ? and `PARTNERS` is not null' at line 11
PARTERS is the column name which I add filter to.
It's very easy to reproduce the problem. In MariaDB just create a table like this:
create table test (name varchar(256), score int(11));
then, insert two rows:
insert into test values ('john', 90);
insert into test values ('nick', 80);
To get data from MariaDB in PowerBI, import 'test' table then click 'transform data'. In resulting Power Query Editor, add text filter for name 'nick'. Then close & load.
That's all, I hope you could reproduce the problem, and fix it SOON!
(In my opnion, it's related with length of VARCHAR. VARCHAR(10) column did not raised the problem)