对比图完成

pages/api/sh300-index.js

@@ -22,30 +22,27 @@ async function handler(req, res) {
     const params = [];
     const conditions = [];
 
-    if (startDate) {
-      conditions.push('date >= ?');
-      params.push(startDate);
-    }
-
-    if (endDate) {
-      conditions.push('date <= ?');
-      params.push(endDate);
+    if (startDate && endDate) {
+      conditions.push('date BETWEEN ? AND ?');
+      params.push(startDate, endDate);
     }
 
     if (conditions.length > 0) {
       query += ' WHERE ' + conditions.join(' AND ');
     }
 
-    query += ' ORDER BY date ASC';
-
-    if (limit) {
-      query += ' LIMIT ?';
-      params.push(parseInt(limit));
-    }
+    query += ' ORDER BY date DESC';
 
     const result = await pool.query(query, params);
 
-    const data = result.map(row => {
+    // 限制返回数量，默认为30
+    const limitValue = limit ? parseInt(limit) : 30;
+    const limitedResult = result.slice(0, limitValue);
+    
+    // 反转顺序，使日期从早到晚
+    const sortedResult = limitedResult.reverse();
+
+    const data = sortedResult.map(row => {
       let dateStr;
       if (row.date instanceof Date) {
         dateStr = row.date.toISOString().split('T')[0];