Add MySQL query solution to README_EN.md

Added MySQL solution for human traffic analysis in stadium.

Author: hhnguyen-20

solution/0600-0699/0601.Human Traffic of Stadium/README_EN.md

@@ -104,4 +104,35 @@ ORDER BY 1;
 
 <!-- solution:end -->
 
+<!-- solution:start -->
+
+### Solution 2
+
+<!-- tabs:start -->
+
+#### MySQL
+
+```sql
+# Write your MySQL query statement below
+WITH Consecutive AS (
+    SELECT 
+        *, 
+        id - ROW_NUMBER() OVER() AS id_diff
+    FROM Stadium
+    WHERE people >= 100
+)
+SELECT id, visit_date, people
+FROM Consecutive
+WHERE id_diff IN (
+    SELECT id_diff 
+    FROM Consecutive 
+    GROUP BY id_diff HAVING COUNT(*) > 2
+)
+ORDER BY visit_date;
+```
+
+<!-- tabs:end -->
+
+<!-- solution:end -->
+
 <!-- problem:end -->