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Upgrade course error -- selectrow_array failed: fetch() without execute()

Upgrade course error -- selectrow_array failed: fetch() without execute()

by Jeremy Lounds -
Number of replies: 1
Hello,

We are testing WeBWorK 2.14, but are receiving an error on the "Upgrade Courses" admin page.

In addition to upgrading from 2.13 to 2.14, we are moving to a Percona MySQL cluster, which required us to convert all databases from MyISAM to InnoDB, and to add primary keys on tables that did not have them. I am not sure if those changes could have caused this?

Warning messages

  • (in cleanup) DBD::mysql::db selectrow_array failed: fetch() without execute() at /opt/webwork/webwork2/lib/WeBWorK/Utils/CourseIntegrityCheck.pm line 419.

Error messages

DBD::mysql::db selectrow_array failed: fetch() without execute() at /opt/webwork/webwork2/lib/WeBWorK/Utils/CourseIntegrityCheck.pm line 406.

Call stack

The information below can help locate the source of the problem.

  • in WeBWorK::Utils::CourseIntegrityCheck::unlock_database called at line 77 of /opt/webwork/webwork2/lib/WeBWorK/Utils/CourseIntegrityCheck.pm
  • in WeBWorK::Utils::CourseIntegrityCheck::DESTROY called at line 406 of /opt/webwork/webwork2/lib/WeBWorK/Utils/CourseIntegrityCheck.pm
  • in (eval) called at line 406 of /opt/webwork/webwork2/lib/WeBWorK/Utils/CourseIntegrityCheck.pm
  • in Apache::WeBWorK::handler called at line 0 of -e
  • in (eval) called at line 0 of -e
In reply to Jeremy Lounds

Re: Upgrade course error -- selectrow_array failed: fetch() without execute()

by Jeremy Lounds -
Ah, I think I see the problem -- the Percona MySQL cluster does not support locking tables, which the Upgrade Course procedure uses when checking and upgrading table schemas.