Hello,
When updating to CSVI 7.5.1 version if by chance you see a error like below on installation, apply the attached patch with the post using CSVI Maintenance page and then go to CSVI About page and click on Fix Database button. This will solve all the database errors occured installation.
ALTER TABLE `#__csvi_sefurls` MODIFY `plainurl` VARCHAR(512) ;. This generates the error Index column size too large. The maximum column size is 767 bytes.
patch_database_size_error_2018_04_12.zip