使用Java和SQL删除两个表中的行

我已将Java连接到SQL，并希望从不同的表中删除两行，但我的Java方法有问题。我正试图从两个表中删除ID，因为它被表2引用，所以无法从表1中删除ID。有没有解决这个问题的建议

public void delete() throws SQLException
    {
        DataConnection connection = new DataConnection();

        String query = " DELETE FROM " + Table1 + " WHERE ID = " + id + " AND " + " DELETE FROM " + Table2 + " WHERE ID = " + id;
        connection.updateData(query);
        connection.closeConnection();
    }

---

按此顺序逐个执行查询，不能在一个查询中执行-

String s2 =  " DELETE FROM table2 WHERE ID = " + id;
// Execute s2 here

String s1 = "Delete from table1  WHERE ID = " + id  ;
// Execute s1 here

试试这个-

public void delete() throws SQLException {
    DataConnection connection = new DataConnection();
    String query1 = " DELETE FROM " + table2 + " WHERE ID = " + id;
    String query2 = " DELETE FROM " + Table1 + " WHERE ID = " + id;
    //  String query = query1 + " " + query2;
    connection.updateData(query1);
    connection.updateData(query2);
    connection.closeConnection();

---

按此顺序逐个执行查询，不能在一个查询中执行-

String s2 =  " DELETE FROM table2 WHERE ID = " + id;
// Execute s2 here

String s1 = "Delete from table1  WHERE ID = " + id  ;
// Execute s1 here

试试这个-

public void delete() throws SQLException {
    DataConnection connection = new DataConnection();
    String query1 = " DELETE FROM " + table2 + " WHERE ID = " + id;
    String query2 = " DELETE FROM " + Table1 + " WHERE ID = " + id;
    //  String query = query1 + " " + query2;
    connection.updateData(query1);
    connection.updateData(query2);
    connection.closeConnection();

---

按此顺序逐个执行查询，不能在一个查询中执行-

String s2 =  " DELETE FROM table2 WHERE ID = " + id;
// Execute s2 here

String s1 = "Delete from table1  WHERE ID = " + id  ;
// Execute s1 here

试试这个-

public void delete() throws SQLException {
    DataConnection connection = new DataConnection();
    String query1 = " DELETE FROM " + table2 + " WHERE ID = " + id;
    String query2 = " DELETE FROM " + Table1 + " WHERE ID = " + id;
    //  String query = query1 + " " + query2;
    connection.updateData(query1);
    connection.updateData(query2);
    connection.closeConnection();

---

按此顺序逐个执行查询，不能在一个查询中执行-

String s2 =  " DELETE FROM table2 WHERE ID = " + id;
// Execute s2 here

String s1 = "Delete from table1  WHERE ID = " + id  ;
// Execute s1 here

试试这个-

public void delete() throws SQLException {
    DataConnection connection = new DataConnection();
    String query1 = " DELETE FROM " + table2 + " WHERE ID = " + id;
    String query2 = " DELETE FROM " + Table1 + " WHERE ID = " + id;
    //  String query = query1 + " " + query2;
    connection.updateData(query1);
    connection.updateData(query2);
    connection.closeConnection();

---

使您的方法可重用：

public void delete(String table, long id) throws SQLException {
    DataConnection connection = new DataConnection();

    String query = " DELETE FROM " + table + " WHERE ID = " + id;
    connection.updateData(query);

    connection.closeConnection();
}

然后调用：

delete(Table1, id);
delete(Table2, id);

---

但这取决于创建新连接的成本。

使您的方法可重用：

public void delete(String table, long id) throws SQLException {
    DataConnection connection = new DataConnection();

    String query = " DELETE FROM " + table + " WHERE ID = " + id;
    connection.updateData(query);

    connection.closeConnection();
}

然后调用：

delete(Table1, id);
delete(Table2, id);

---

但这取决于创建新连接的成本。

使您的方法可重用：

public void delete(String table, long id) throws SQLException {
    DataConnection connection = new DataConnection();

    String query = " DELETE FROM " + table + " WHERE ID = " + id;
    connection.updateData(query);

    connection.closeConnection();
}

然后调用：

delete(Table1, id);
delete(Table2, id);

---

但这取决于创建新连接的成本。

使您的方法可重用：

public void delete(String table, long id) throws SQLException {
    DataConnection connection = new DataConnection();

    String query = " DELETE FROM " + table + " WHERE ID = " + id;
    connection.updateData(query);

    connection.closeConnection();
}

然后调用：

delete(Table1, id);
delete(Table2, id);

---

---

但这取决于创建新连接的成本。

先从表2删除，然后从表1删除。先从表2删除，然后从表1删除。先从表2删除，然后从表1删除。我尝试了此操作，但出现了错误，因此尝试了以下操作：public void delete（）抛出SQLException{DataConnection connection=newdataconnection（）；String query1=“从“+table2+”中删除，其中ID=“+ID；String query2=“从“+Table1+”中删除，其中ID=“+ID；String query=query1+”+query2；connection.updateData（query）；connection.closeConnection（）；}我尝试了此操作并出现错误，因此尝试了以下操作：public void delete（）抛出SQLException{DataConnection connection=new DataConnection（）；String query1=“delete FROM”+table2+”WHERE ID=“+ID；String query2=”delete FROM”+Table1+”WHERE ID=“+ID；String query=query1+”“+query2；connection.updateData（query）；connection.closeConnection（）；}我尝试了此操作，但出现了错误，因此尝试了以下操作：public void delete（）抛出SQLException{DataConnection connection=new DataConnection（）；String query1=“delete FROM”+table2+”其中ID=“+ID；String query2=“delete FROM”+Table1+“WHERE ID=“+ID；String query=query1+”+query2；connection.updateData（query）；connection.closeConnection（）；}我尝试了此操作，但出现了错误，因此尝试了以下操作：public void delete（）抛出SQLException{DataConnection connection=new DataConnection（）；String query1=“delete FROM”+table2+“WHERE ID=“+ID；String query2=”从“+Table1+”WHERE ID=“+ID；String query=query1+”+query2；connection.updateData（query）；connection.closeConnection（）；}好的，我从表2中删除，但它仍然不允许我从表1中删除。有什么建议吗？除了表2之外，还有其他表1的参考表吗？那么你也必须删除该表，否则你不能删除表1谢谢你的帮助，我感谢你的时间！！好的，我从表2中删除，但它仍然没有I don’我不允许从表1中删除。对方法有任何建议吗？除了表2之外，还有其他表1的参考表吗？那么你也必须删除该表，否则你不能删除表1谢谢你的帮助，我感谢你抽出时间！！好的，我从表2中删除了，但它仍然不允许我从表1中删除。有什么建议吗n方法？除了表2，还有其他表1的参考表吗？那么你也必须删除该表，否则你不能删除表1谢谢你的帮助，我感谢你的时间！！好的，我从表2中删除了，但它仍然不允许我从表1中删除。对方法有什么建议吗？还有其他的参考表吗r表1除了表2？那么你也必须删除该表，否则你不能删除表1谢谢你的帮助，我感谢你的时间！！嗨@Ivan Babanin删除（表1，id）到哪里去了？我创建这个，这样用户就可以不用写代码就删除了。嗨@Ivan Babanin删除（表1，id）到哪里去了go？我创建它是为了让用户可以不写代码就删除。Hi@Ivan Babanin删除（表1，id）到哪里去了？我创建它是为了让用户可以不写代码就删除。Hi@Ivan Babanin删除（表1，id）到哪里去了？我创建它是为了让用户可以不写代码就删除。