diff --git a/src/com/hellogithub/dao/UserDao.java b/src/com/hellogithub/dao/UserDao.java
index 024cd11..4267e3c 100644
--- a/src/com/hellogithub/dao/UserDao.java
+++ b/src/com/hellogithub/dao/UserDao.java
@@ -92,7 +92,7 @@ public class UserDao {
         Connection connection = null;
         try {
             connection = JdbcUtils.getConnection();
-            String loginSql = "select  * from  user where userName=?";
+            String loginSql = "select  * from  user where userName=? and isValid = 1";
             preparedStatement = connection.prepareStatement(loginSql);
             preparedStatement.setString(1, userName);
             resultSet = preparedStatement.executeQuery();
@@ -123,7 +123,7 @@ public class UserDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select searchHistory from user where userName=?";
+            String sql = "select searchHistory from user where userName=? and isValid = 1";
             userEntity  = runner.query(conn, sql, new BeanHandler<>(userEntity.class),name);
             label = userEntity.getSearchHistory().replace(str+";","");
             sql="UPDATE user SET searchHistory = ? WHERE userName= ?";
@@ -144,7 +144,7 @@ public class UserDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select searchHistory from user where userName=?";
+            String sql = "select searchHistory from user where userName=? and isValid = 1";
             userEntity1  = runner.query(conn, sql, new BeanHandler<>(userEntity.class),name);
             label=userEntity1.getSearchHistory();
         } catch (SQLException e) {
@@ -164,7 +164,7 @@ public class UserDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql="UPDATE user SET searchHistory = ? WHERE userName= ?";
+            String sql="UPDATE user SET searchHistory = ? WHERE userName= ? and isValid = 1";
             num = runner.update(conn,sql,label,name);
         } catch (SQLException e) {
             throw new RuntimeException(e);
@@ -183,7 +183,7 @@ public class UserDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql="select count(*) as num from user";
+            String sql="select count(*) as num from user where isValid = 1";
             userEntity = runner.query(conn,sql,new BeanHandler<>(userEntity.class));
             num = userEntity.getNum();
         } catch (SQLException e) {
@@ -201,7 +201,7 @@ public class UserDao {
         Connection conn = null;
         PreparedStatement preparedStatement = null;
         ResultSet rs = null;
-        String sql = "SELECT * FROM `user` t1,article t2 WHERE t1.userId = t2.userId AND t1.userId = ?";
+        String sql = "SELECT * FROM `user` t1,article t2 WHERE t1.userId = t2.userId AND t1.userId = ? and isValid = 1";
         int Value = 0;
         try{
             conn = JdbcUtils.getConnection();
@@ -239,10 +239,10 @@ public class UserDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select searchHistory from user where userName=?";
+            String sql = "select searchHistory from user where userName=? and isValid = 1";
             userEntity  = runner.query(conn, sql, new BeanHandler<>(userEntity.class),username);
             label = userEntity.getSearchHistory()+str+";";
-            sql="UPDATE user SET searchHistory = ? WHERE userName= ?";
+            sql="UPDATE user SET searchHistory = ? WHERE userName= ? and isValid = 1";
             num = runner.update(conn,sql,label,username);
         } catch (SQLException e) {
             throw new RuntimeException(e);
diff --git a/src/com/hellogithub/dao/articleDao.java b/src/com/hellogithub/dao/articleDao.java
index 3629a4c..401ad1e 100644
--- a/src/com/hellogithub/dao/articleDao.java
+++ b/src/com/hellogithub/dao/articleDao.java
@@ -24,7 +24,7 @@ public class articleDao {
         Connection conn = null;
         PreparedStatement preparedStatement = null;
         ResultSet rs = null;
-        String sql = "SELECT * FROM `article` ORDER BY publishTime DESC;";
+        String sql = "SELECT * FROM `article` where isValid = 1 ORDER BY publishTime DESC;";
         ArrayList<com.hellogithub.entity.articleEntity> articleEntities = new ArrayList<articleEntity>();
         try {
             conn = JdbcUtils.getConnection();
@@ -62,7 +62,7 @@ public class articleDao {
         Connection conn = null;
         PreparedStatement preparedStatement = null;
         ResultSet rs = null;
-        String sql = "SELECT * FROM `article` ORDER BY readCount DESC";
+        String sql = "SELECT * FROM `article` where isValid = 1 ORDER BY readCount DESC";
         ArrayList<com.hellogithub.entity.articleEntity> articleEntities = new ArrayList<articleEntity>();
         try {
             conn = JdbcUtils.getConnection();
diff --git a/src/com/hellogithub/dao/categoryDao.java b/src/com/hellogithub/dao/categoryDao.java
index 192960b..27b8ef6 100644
--- a/src/com/hellogithub/dao/categoryDao.java
+++ b/src/com/hellogithub/dao/categoryDao.java
@@ -19,7 +19,7 @@ public class categoryDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select * from category ";
+            String sql = "select * from category where isValid = 1";
             categoryEntity = runner.query(conn, sql, new BeanListHandler<>(categoryEntity.class));
             conn.close();
         } catch (SQLException e) {
@@ -33,7 +33,7 @@ public class categoryDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select * from category where categoryId=?";
+            String sql = "select * from category where categoryId=? and isValid = 1";
             categoryEntity = runner.query(conn, sql, new BeanHandler<>(categoryEntity.class),id);
             conn.close();
         } catch (SQLException e) {
diff --git a/src/com/hellogithub/dao/projectDao.java b/src/com/hellogithub/dao/projectDao.java
index 586602a..74bde94 100644
--- a/src/com/hellogithub/dao/projectDao.java
+++ b/src/com/hellogithub/dao/projectDao.java
@@ -213,7 +213,7 @@ public class projectDao {
         try {
             Connection conn = JdbcUtils.getConnection();
             QueryRunner runner = new QueryRunner();
-            String sql = "select categoryName from category where categoryId in( select categoryId from project_category where projectId = ?)";
+            String sql = "select categoryName from category where isValid = 1 and categoryId in( select categoryId from project_category where projectId = ? and  isValid = 1)";
             categoryEntityList = runner.query(conn, sql,new BeanListHandler<>(categoryEntity.class),id);
             conn.close();
         } catch (SQLException e) {