Class with id 131 doesn't exist.
Query:
SELECT `Field_ID` as `id`, `Field_Name` as `name`, `TypeOfData_ID` as `type`, `Format` as `format`, `Description` AS `description`, `NotNull` AS `not_null`, `DefaultState` as `default`, `TypeOfEdit_ID` AS `edit_type`, IF(`TypeOfData_ID` IN (4, 10), SUBSTRING_INDEX(`Format`, ':', 1), '') AS `table`, `DoSearch` AS `search` FROM `Field` WHERE `Checked` = 1 AND `Class_ID` = '131' ORDER BY `Priority`
Error:
MySQL server has gone away