diff --git a/server/internal/api/exports.go b/server/internal/api/exports.go
index 55fb03d..c8260f9 100644
--- a/server/internal/api/exports.go
+++ b/server/internal/api/exports.go
@@ -156,23 +156,34 @@ func (a *ExportsAPI) create(w http.ResponseWriter, r *http.Request) {
 	// 注意：不再从 URL 参数 userId 或 current_user_id 自动转换为 creator_in 过滤
 	// current_user_id 仅用于记录导出任务的 owner，不用于数据过滤
 	// support multiple merchantId in query: e.g., merchantId=1,2,3 → filters.merchant_id_in
+	// 注意：对于 YMT 数据源，reseller_id_eq 和 merchant_id_in 映射到同一物理列 order_info.merchant_id，
+	// 当 reseller_id_eq 已存在且非零时，跳过 merchantId URL 参数注入以避免冲突导致过滤条件丢失
 	{
-		midStr := r.URL.Query().Get("merchantId")
-		if midStr != "" {
-			parts := strings.Split(midStr, ",")
-			ids := make([]interface{}, 0, len(parts))
-			for _, s := range parts {
-				s = strings.TrimSpace(s)
-				if s == "" {
-					continue
+		skipMerchantIdIn := false
+		// 当 reseller_id_eq 已存在且非零时，跳过 merchantId URL 参数注入
+		// YMT: reseller_id_eq 和 merchant_id_in 映射同一物理列 order_info.merchant_id，注入会导致冲突
+		// Marketing: merchant_id_in 未在 schema 中定义，但其存在会阻止 reseller_id_eq 的应用
+		if v, ok := p.Filters["reseller_id_eq"]; ok && v != nil && v != "" && v != 0 {
+			skipMerchantIdIn = true
+		}
+		if !skipMerchantIdIn {
+			midStr := r.URL.Query().Get("merchantId")
+			if midStr != "" {
+				parts := strings.Split(midStr, ",")
+				ids := make([]interface{}, 0, len(parts))
+				for _, s := range parts {
+					s = strings.TrimSpace(s)
+					if s == "" {
+						continue
+					}
+					if n, err := strconv.ParseUint(s, 10, 64); err == nil {
+						ids = append(ids, n)
+					}
 				}
-				if n, err := strconv.ParseUint(s, 10, 64); err == nil {
-					ids = append(ids, n)
-				}
-			}
-			if len(ids) > 0 {
-				if _, exists := p.Filters["merchant_id_in"]; !exists {
-					p.Filters["merchant_id_in"] = ids
+				if len(ids) > 0 {
+					if _, exists := p.Filters["merchant_id_in"]; !exists {
+						p.Filters["merchant_id_in"] = ids
+					}
 				}
 			}
 		}
diff --git a/server/internal/exporter/sqlbuilder.go b/server/internal/exporter/sqlbuilder.go
index 041d0aa..908d74d 100644
--- a/server/internal/exporter/sqlbuilder.go
+++ b/server/internal/exporter/sqlbuilder.go
@@ -317,6 +317,13 @@ func BuildSQLWithFields(req BuildRequest, whitelist map[string]bool) (string, []
 			where = append(where, fmt.Sprintf("`%s`.%s IN (%s)", sch.TableName(tbl), escape(col), ph))
 			args = append(args, creatorArgs...)
 		}
+	} else if hasMerchant {
+		if tbl, col, ok := sch.FilterColumn("merchant_id_in"); ok {
+			ph := strings.Repeat("?,", len(merchantArgs))
+			ph = strings.TrimSuffix(ph, ",")
+			where = append(where, fmt.Sprintf("`%s`.%s IN (%s)", sch.TableName(tbl), escape(col), ph))
+			args = append(args, merchantArgs...)
+		}
 	}
 
 	if v, ok := req.Filters["create_time_between"]; ok {
@@ -647,6 +654,13 @@ func BuildCountSQL(req BuildRequest, whitelist map[string]bool) (string, []inter
 			where = append(where, fmt.Sprintf("`%s`.%s IN (%s)", sch.TableName(tbl), escape(col), ph))
 			args = append(args, creatorArgs...)
 		}
+	} else if hasMerchant {
+		if tbl, col, ok := sch.FilterColumn("merchant_id_in"); ok {
+			ph := strings.Repeat("?,", len(merchantArgs))
+			ph = strings.TrimSuffix(ph, ",")
+			where = append(where, fmt.Sprintf("`%s`.%s IN (%s)", sch.TableName(tbl), escape(col), ph))
+			args = append(args, merchantArgs...)
+		}
 	}
 
 	// build WHERE from other filters