I am trying to upgrade but I am stuck at this error
(mysqli): ALTER TABLE users MODIFY COLUMN user_id BIGINT NOT NULL AUTO_INCREMENT
Query: ALTER TABLE users MODIFY COLUMN user_id BIGINT NOT NULL AUTO_INCREMENT failed. Incorrect table definition; there can be only one auto column and it must be defined as a key
1075: Incorrect table definition; there can be only one auto column and it must be defined as a key
ADOConnection._Execute(ALTER TABLE users MODIFY COLUMN user_id BIGINT NOT NULL AUTO_INCREMENT, false) % line 1051, file: adodb.inc.php
ADOConnection.Execute(ALTER TABLE users MODIFY COLUMN user_id BIGINT NOT NULL AUTO_INCREMENT) % line 440, file: Installer.inc.php
Installer.executeSQL(ALTER TABLE users MODIFY COLUMN user_id BIGINT NOT NULL AUTO_INCREMENT) % line 435, file: Installer.inc.php
Installer.executeSQL(Array[176]) % line 375, file: Installer.inc.php
Installer.executeAction(Array[3]) % line 265, file: Installer.inc.php
Following topic shows a fix applied by a user to a issue like yours:
Although consider an upgrade to latest 2.4.x version before go to OJS3, it will bring all minor code release/fix and it will be more compatible in upgrade process to OJS 3.x version.
Regards,
Israel Cefrin
Public Knowledge Project Team