backup.pl fails when source db is mysql 5.7 and destination db is mysql 8.0

[OlliW]

then i have to set the parameter column-statistics

mysqldump --column-statistics=0

[bschmalhofer]

Hi @OlliW ,

it looks like the problem is that on some versions of mysqldump the column-statistics feature is turned on by default. And on some versions of mysqldump this leads to an error when the table information_schema.COLUMN_STATISTICS does not exist. Under MySQL 5.7 this table usually does not exists.

As this is an effect that occurs only under specific circumstances I'm hesitant to add --column-statistics=0 permanently to the dump command. Instead I'll add an apption for passing extra options to the dump command. Adding a --dry-run option for printing out the dump commands seems to be useful too.

[bschmalhofer]

Hi @OlliW ,

I adapted scripts/backup.pl in the branch https://github.com/RotherOSS/otobo/tree/issue-%23884-no_column_statistics . The plan is to integrate this into OTOBO 10.0.10, but we need to test first.

Best regards,
Bernhard

[bschmalhofer]

Changes are merged now. Tests are pending.

[svenoe]

At least a standard migration passed.