I keep randomly getting this error within my Drupal site. Only way to resolve is to delete the session from the database.
PDOException: SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded; try restarting transaction: SELECT revision.order_number AS order_number, revision.revision_id AS revision_id, revision.revision_uid AS revision_uid, revision.mail AS mail, revision.status AS status, revision.log AS log, revision.revision_timestamp AS revision_timestamp, revision.revision_hostname AS revision_hostname, revision.data AS data, base.order_id AS order_id, base.type AS type, base.uid AS uid, base.created AS created, base.changed AS changed, base.hostname AS hostname FROM {commerce_order} base INNER JOIN {commerce_order_revision} revision ON revision.revision_id = base.revision_id WHERE (base.order_id IN (:db_condition_placeholder_0)) FOR UPDATE; Array ( [:db_condition_placeholder_0] => 1 ) in DrupalDefaultEntityController->load() (line 196 of C:\Sites\includes\entity.inc).
Do you have any idea what is wrong?