扩充摘要信息长度

src/main/java/com/bupt/note/Model/Paper.java

@@ -88,7 +88,7 @@ public class Paper {
         this.year = year;
     }
 
-    @Column(nullable = false)
+    @Column(nullable = false,length = 512)
     public String getSummary() {
         return summary;
     }