更新

src/com/hellogithub/dao/UserDao.java

@@ -144,7 +144,7 @@ public class UserDao {
             {
                 label = String.join(";",sss)+";";
             }else{
-                label="";
+                label=null;
             }
             sql="UPDATE user SET searchHistory = ? WHERE userName= ?";
             num = runner.update(conn,sql,label,name);

src/com/hellogithub/servlet/deletelabelServlet.java

@@ -43,9 +43,9 @@ public class deletelabelServlet extends HttpServlet {
         int num = userService.dedletePieceLabel(name,str);
         //返回处理行数，如果为零则代表处理零条结果
         if(num == 0 ){
-            setResultError("删除失败1",writer);
+            setResultError("删除失败",writer);
         }else{
-            setResultOK("删除成功1",writer);
+            setResultOK("删除成功",writer);
         }
     }
     public void setResult(Integer code, String msg, PrintWriter writer) {