From 83339f42a306bbec60e545a4ac88b5a380a083c0 Mon Sep 17 00:00:00 2001
From: zhouyonggao <1971162852@qq.com>
Date: Wed, 17 Dec 2025 19:58:28 +0800
Subject: [PATCH] =?UTF-8?q?feat(exports):=20=E5=A2=9E=E5=BC=BA=E8=A1=8C?=
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- 在create函数中添加行数估算逻辑，优先使用分块统计，失败时回退到精确COUNT
- 添加日志记录以跟踪估算过程，确保在估算为0时能够进行精确统计
- 提升代码可读性，确保行数估算和日志记录逻辑清晰明了
---
 server/internal/api/exports.go | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/server/internal/api/exports.go b/server/internal/api/exports.go
index 5494fee..15acdb9 100644
--- a/server/internal/api/exports.go
+++ b/server/internal/api/exports.go
@@ -305,8 +305,18 @@ func (a *ExportsAPI) create(w http.ResponseWriter, r *http.Request) {
 		fail(w, r, http.StatusBadRequest, fmt.Sprintf("EXPLAIN 未通过：评分=%d，请优化索引或缩小查询范围", score))
 		return
 	}
+	// 估算行数（优先使用分块统计，失败或结果为 0 时回退到单次 COUNT）
 	var estimate int64
 	estimate = rrepo.EstimateFastChunked(dataDB, ds, main, p.Filters)
+	if estimate <= 0 {
+		logging.JSON("WARN", map[string]interface{}{
+			"event":      "estimate_zero_fallback",
+			"datasource": ds,
+			"main_table": main,
+			"filters":    p.Filters,
+		})
+		estimate = rrepo.EstimateFast(dataDB, ds, main, p.Filters)
+	}
 	hdrs := make([]string, len(filtered))
 	for i, tf := range filtered {
 		if v, ok := labels[tf]; ok {