https://confluence.atlassian.com/display/JIRA/Retrieving+the+JIRA+Administrator

In the section about "adding groups to the appropriate global permissions" the SQL that is supposed to add the group to the appropriate global permission doesn't actually do that. Here's the code:

insert into schemepermissions (id, scheme, permission, perm_type, perm_parameter) values (444444,NULL,44,'group','jira-administrators');
insert into schemepermissions (id, scheme, permission, perm_type, perm_parameter) values (333333,NULL,1,'group','jira-users');

The schemepermissions table doesn't actually grant the global permission for JIRA System Administrators. That permission is actually granted in the globalpermissionentry table. Only performing this insert will grant that global permission:

INSERT INTO globalpermissionentry(id, permission, group_id) 
VALUES (444444, 'SYSTEM_ADMIN', 
'jira-administrators');