-- t_order 预报失败原因（可重复执行）
-- 在 OMS 业务库执行：mysql -h<host> -u<user> -p<db> < migrate_t_order_predeclare_fail_reason.sql

SET @db = DATABASE();

SET @exist := (SELECT COUNT(*) FROM information_schema.COLUMNS
    WHERE TABLE_SCHEMA = @db AND TABLE_NAME = 't_order' AND COLUMN_NAME = 'PredeclareFailReason');
SET @sql := IF(@exist = 0,
    'ALTER TABLE `t_order` ADD COLUMN `PredeclareFailReason` VARCHAR(512) NULL COMMENT ''预报失败原因'' AFTER `IsRemote`',
    'SELECT ''skip PredeclareFailReason''');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;