-- 计量单位新增计量单位编码
ALTER TABLE `blade_measurement_unit`
  ADD COLUMN `unit_code` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '计量单位编码' AFTER `id`;

UPDATE `blade_measurement_unit`
SET `unit_code` = CONCAT('MU', `id`)
WHERE `unit_code` IS NULL OR `unit_code` = '';

ALTER TABLE `blade_measurement_unit`
  MODIFY COLUMN `unit_code` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '计量单位编码',
  ADD UNIQUE INDEX `uk_measurement_unit_code`(`unit_code`) USING BTREE;