Thanks Emma a lot,
Finally, I upgraded my site successfully. It was a struggle because I had to rename many tables such as; qtype_ and tool_monitor_. And now I see in my database having a lot of _old tables. I wonder whether this way will affect my site in the future or not. Should I drop all old tables?
Plz have a look at my database
And
+ It looks like a mess!
Thanks again,
Ok, so what you need to do now is verify everything is working correctly. You need to go into a question of each type and verify that you can edit them. That will show you that the data has transposed to the new table correctly.
Also check your tool monitor as well.
Once you have verified that the data has come into the new table (you can also open the new tables and verify the data is there but I recommend checking functionality too), you can delete the old ones.
For any ones that have not created a new table (off the top of my head I see ddmarker_drops) just rename the old table back to its original name. (This might not have been created because you don't have any questions of this type but occasionally the table will not recreate properly so this method ensures that you don't lose any of your questions)
I do as you told me. Everything seems to work correctly up to now. However, I wonder whether my site will work correctly or not in the future. And I'm also afraid that I'll get errors like this when upgrading higher versions.
Thanks Emma so much again,