diff --git a/server/internal/exporter/stream.go b/server/internal/exporter/stream.go
index c837666..3d3fbb1 100644
--- a/server/internal/exporter/stream.go
+++ b/server/internal/exporter/stream.go
@@ -158,7 +158,7 @@ func CountRowsFast(db *sql.DB, ds, main string, filters map[string]interface{})
 	}
 	// 记录行数统计 SQL，方便排查估算问题
 	logging.JSON("INFO", map[string]interface{}{
-		"event":     "count_fast_query",
+		"event":      "count_fast_query",
 		"datasource": ds,
 		"main":       main,
 		"sql":        q,
diff --git a/server/internal/schema/ymt.go b/server/internal/schema/ymt.go
index 07687e2..869a1aa 100644
--- a/server/internal/schema/ymt.go
+++ b/server/internal/schema/ymt.go
@@ -52,16 +52,20 @@ func (s ymtSchema) MapField(t, f string) (string, bool) {
 func (s ymtSchema) BuildJoins(need map[string]bool, main string) []string {
 	out := []string{}
 	if need["order_cash"] {
-		out = append(out, " LEFT JOIN `order_cash` ON `order_cash`.order_no = `order_info`.order_no")
+		// MySQL 8 窗口函数去重，取每个订单的第一条记录
+		out = append(out, " LEFT JOIN (SELECT *, ROW_NUMBER() OVER (PARTITION BY order_no ORDER BY id) AS rn FROM `order_cash`) AS `order_cash` ON `order_cash`.order_no = `order_info`.order_no AND `order_cash`.rn = 1")
 	}
 	if need["order_voucher"] {
-		out = append(out, " LEFT JOIN `order_voucher` ON `order_voucher`.order_no = `order_info`.order_no")
+		// MySQL 8 窗口函数去重，取每个订单的第一条记录
+		out = append(out, " LEFT JOIN (SELECT *, ROW_NUMBER() OVER (PARTITION BY order_no ORDER BY id) AS rn FROM `order_voucher`) AS `order_voucher` ON `order_voucher`.order_no = `order_info`.order_no AND `order_voucher`.rn = 1")
 	}
 	if need["order_digit"] {
-		out = append(out, " LEFT JOIN `order_digit` ON `order_digit`.order_no = `order_info`.order_no")
+		// MySQL 8 窗口函数去重，取每个订单的第一条记录
+		out = append(out, " LEFT JOIN (SELECT *, ROW_NUMBER() OVER (PARTITION BY order_no ORDER BY id) AS rn FROM `order_digit`) AS `order_digit` ON `order_digit`.order_no = `order_info`.order_no AND `order_digit`.rn = 1")
 	}
 	if need["goods_voucher_batch"] {
-		out = append(out, " LEFT JOIN `goods_voucher_batch` ON `goods_voucher_batch`.channel_batch_no = `order_voucher`.channel_batch_no")
+		// MySQL 8 窗口函数去重
+		out = append(out, " LEFT JOIN (SELECT *, ROW_NUMBER() OVER (PARTITION BY channel_batch_no ORDER BY id) AS rn FROM `goods_voucher_batch`) AS `goods_voucher_batch` ON `goods_voucher_batch`.channel_batch_no = `order_voucher`.channel_batch_no AND `goods_voucher_batch`.rn = 1")
 	}
 	if need["goods_voucher_subject_config"] {
 		out = append(out, " LEFT JOIN `goods_voucher_subject_config` ON `goods_voucher_subject_config`.id = `goods_voucher_batch`.voucher_subject_id")