Thread:Project:Support desk/MediaWiki Update 1.15.3 - 1.20.3: Update script causes error

Hello everyone.

While updating my Wiki from version 1.15.3 to 1.20.3 the update script gives this error: Adding index ls_field_val to table log_search ... An error occurred: Es gab einen Syntaxfehler in der Datenbankabfrage. Die letzte Datenbankabfrage lautete: „ALTER TABLE `log_search` DROP PRIMARY KEY, ADD UNIQUE INDEX ls_field_val (ls_field,ls_value,ls_log_id) “ aus der Funktion „DatabaseBase::sourceFile( /srv/www/vhosts/freeway-gmbh.com/subdomains /wiki/httpdocs/maintenance/archives/patch-log_search-rename-index.sql )“. Die Datenbank meldete den Fehler: „1091: Can't DROP 'PRIMARY'; check that column/key exists (localhost)“. PHP 5.4.11, MySQL 5.4.11 (cgi-fcgi).

What can I do? I prefer the web updater (yes, I know... :D).