ALTER TABLE `equipment` ADD `calibration_frequency_external` TEXT NOT NULL AFTER `calibration_frequency`;
ALTER TABLE `equipment` ADD `calibration_frequency_inhouse` TEXT NOT NULL AFTER `calibration_frequency`
ALTER TABLE `equipment` ADD `preventive_maintenance` VARCHAR(15) NOT NULL AFTER `calibration_type`;
ALTER TABLE `equipment` ADD `inpection_freequency` VARCHAR(500) NOT NULL AFTER `lastcalibration_date`, ADD `prev_maint_frequency` VARCHAR(500) NOT NULL AFTER `inpection_freequency`;
ALTER TABLE `equipment` ADD `last_inspection_date` DATE NOT NULL AFTER `prev_maint_frequency`, ADD `last_prev_maint_date` DATE NOT NULL AFTER `last_inspection_date`;