-- TMS 订单状态查询接口：为运单号精确查询补充索引。
-- 订单号已有唯一索引，转单号已有索引；当前表结构通常缺少 tracking_no 索引。
-- 脚本可重复执行。
SET NAMES utf8mb4;
SET @db_name := DATABASE();

SET @has_tracking_index := (
    SELECT COUNT(*)
    FROM information_schema.STATISTICS
    WHERE TABLE_SCHEMA = @db_name
      AND TABLE_NAME = 'prc_order_bill'
      AND INDEX_NAME = 'idx_order_bill_tracking_no'
);
SET @sql := IF(@has_tracking_index = 0,
    'ALTER TABLE prc_order_bill ADD INDEX idx_order_bill_tracking_no (tracking_no)',
    'SELECT 1');
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

SELECT
    TABLE_NAME,
    INDEX_NAME,
    COLUMN_NAME,
    NON_UNIQUE
FROM information_schema.STATISTICS
WHERE TABLE_SCHEMA = @db_name
  AND TABLE_NAME = 'prc_order_bill'
  AND INDEX_NAME IN ('uk_bill_order', 'idx_order_bill_tracking_no', 'idx_order_bill_transfer_no')
ORDER BY INDEX_NAME, SEQ_IN_INDEX;