How can I Export Warnings generated by HeidiSQL
Learn how to use the commandline "mysql" tool.  Then perform the LOAD and SHOW there.

Example

tee filename can be invoked from the CLI without losing the WARNINGs:

CREATE TABLE dtts (
    ... just_date DATE ... );

mysql&gt; INSERT INTO dtts (just_date) VALUES (NOW());
Query OK, 1 row affected, 1 warning (0.00 sec)

mysql&gt; tee /tmp/mtee
Logging to file '/tmp/mtee'
mysql&gt; SHOW WARNINGS;
+-------+------+------------------------------------------------+
| Level | Code | Message                                        |
+-------+------+------------------------------------------------+
| Note  | 1265 | Data truncated for column 'just_date' at row 1 |
+-------+------+------------------------------------------------+
1 row in set (0.00 sec)

mysql&gt; exit
Bye
rj$ ls -l /tmp/mtee
-rw-rw-r-- 1 rj rj 389 Dec  7 14:05 /tmp/mtee
rj$ cat /tmp/mtee
mysql&gt; SHOW WARNINGS;
+-------+------+------------------------------------------------+
| Level | Code | Message                                        |
+-------+------+------------------------------------------------+
| Note  | 1265 | Data truncated for column 'just_date' at row 1 |
+-------+------+------------------------------------------------+
1 row in set (0.00 sec)

mysql&gt; exit
rj$