Thread:Project:Support desk/Import 1.15 database to 1.19 install/reply (5)

are you absolutely sure that you imported the script generated by mysqldump to the correct database/server instance?

So, you did a mysqldump of the working wiki, and then, where did you imported the generated script? It should be imported on a new mysql instance, not the same one (unless you know what are you doing) because by default it will import the database to the same database name, so if you run the script on the same instance you'll be restoring the backup over the same database, unless you changed the options of mysqldump to not put statements to select a database in the generated script.