Hello, I am trying to upgrade OJS from 2.4.8.3 to 3.1.1.4
[root@sph sph34]# php tools/upgrade.php check
PHP Strict Standards: Declaration of PKPUsageEventPlugin::getEnabled() should be compatible with LazyLoadPlugin::getEnabled($contextId = NULL) in /var/www/sph34/lib/pkp/plugins/generic/usageEvent/PKPUsageEventPlugin.inc.php on line 386
Code version: 3.1.1.4
Database version: 2.4.8.3
Latest version: 3.1.1.4
Database version is older than code version
Run “tools/upgrade.php upgrade” to update
[root@sph sph34]# php tools/upgrade.php upgrade
PHP Strict Standards: Declaration of PKPUsageEventPlugin::getEnabled() should be compatible with LazyLoadPlugin::getEnabled($contextId = NULL) in /var/www/sph34/lib/pkp/plugins/generic/usageEvent/PKPUsageEventPlugin.inc.php on line 386
[pre-install]
[load: upgrade.xml]
[version: 3.1.1.4]
[code: Installer Installer::checkPhpVersion]
[code: Installer Installer::syncSeriesAssocType]
[data: dbscripts/xml/upgrade/2.4.0_preupdate_usageStatistics.xml (skipped)]
[data: dbscripts/xml/upgrade/2.4.0_preupdate_usageStatistics2.xml (skipped)]
[code: Installer Installer::removeReviewEntries]
[data: dbscripts/xml/upgrade/3.0.0_preupdate.xml (skipped)]
[data: dbscripts/xml/upgrade/3.0.0_adaptTimedViews.xml (skipped)]
[data: dbscripts/xml/upgrade/3.0.0_adaptReferrals.xml]
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
[data: dbscripts/xml/upgrade/3.0.0_adaptBooksForReview.xml]
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
[data: dbscripts/xml/upgrade/remove_timed_views_bots.xml (skipped)]
[data: dbscripts/xml/upgrade/3.0.0_preupdate_commentsToEditor.xml (skipped)]
[data: dbscripts/xml/upgrade/3.1.0_preupdate_review_assignments.xml]
Pl help
[data: dbscripts/xml/upgrade/3.0.0_preupdate.xml]
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
PHP Strict Standards: Only variables should be assigned by reference in /var/www/sph34/lib/pkp/classes/db/DBDataXMLParser.inc.php on line 122
ERROR: Upgrade failed: DB: Table ‘articles_migration’ already exists
kindly help on this