You will see an error similar to this:
Specified Key Was Too Long; Max Key Length Is 1000 Bytes
There is a problem that affects a minority of users when installing an extension with this error. This is because of a MySQL bug – a quick search on Google shows the issue.
You will need to revise the SQL file to resolve the issue:
- Disable the extension temporarily to prevent your site from experiencing any more issues in the mean time
- If the the complaint is about the unique keys, go to your SQL install script in
app/code/community/Webshopapps/Productmatrix/sql/productmatrix_setup(using Product Matrix as example) and open the latest version into a text editor
- Find the line declaring
UNIQUE KEYand remove this line. On the
PRIMARY KEYline above, delete the last comma “,” and save
- Upload this over existing install script
- Clear your cache and keep extension disabled
- Refresh the front end
- If no errors are picked up you are resolved
If this does not fix the issue disable the extension by renaming the relevant extension file from
app/etc/modules, to e.g.
Webshopapps_ProductMatrix.xml.orig refresh front end, rename and remove .orig and refresh again.