如何确定使用Java和MySQL的插入或更新是否成功?

I am using Java to connect to a MySQL database. I am trying to insert or update data into the database.

我使用Java连接到一个MySQL数据库。我正在尝试将数据插入或更新到数据库中。

Even though I am quite sure the insert was successful, it returns false.

尽管我很确定插入成功，但它返回false。

According to the "execute" API, the return value is "true if the first result is a ResultSet object; false if it is an update count or there are no results".

根据“execute”API，如果第一个结果是ResultSet对象，则返回值为true;如果是更新计数或没有结果，则为false。

How can I determine whether or not my insert or update was successful?

如何确定插入或更新是否成功?

    public boolean insertSelections(String selection, String name){
        String sql ="INSERT INTO WORKREPORT VALUES (?,?,?,?,?)";
        boolean action = false;
        try {
            PreparedStatement stmt = conn.prepareStatement(sql);
            SimpleDateFormat dateFormat =  new java.text.SimpleDateFormat("yyyy：MM：dd hh:mm:ss");
            String formatDate = dateFormat.format(new java.util.Date(System.currentTimeMillis())); 
            java.util.Date mDate = dateFormat.parse(formatDate);
            java.sql.Timestamp timeStamp = new java.sql.Timestamp(System.currentTimeMillis());
//          Date time= new Date(mDate.getTime());

            stmt.setInt(1, Integer.parseInt(getNumberByName(name).trim()));
            stmt.setString(2, name);
//          stmt.setDate(3, time);
            stmt.setTimestamp(3, timeStamp);
            stmt.setString(4, selection);
            stmt.setString(5, "N/A");
            action = stmt.execute();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }   catch (ParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }   
        return action;
    }

4 个解决方案

#1

Since you are using PreparedStatement you can call executeUpdate() -

由于使用的是PreparedStatement，所以可以调用executeUpdate() -

 int count = stmt.executeUpdate();
 action = (count > 0); // <-- something like this.

From the Javadoc (Returns) link above, emphasis added,

从上面的Javadoc(返回)链接中，强调添加，

either (1) the row count for SQL Data Manipulation Language (DML) statements or (2) 0 for SQL statements that return nothing.

或者(1)对SQL数据操作语言(DML)语句的行计数，或者(2)对于返回无任何值的SQL语句的行数。

If you want to insert a large number of entries, I would prefer addBatch() and executeBatch().

如果您想插入大量的条目，我更喜欢addBatch()和executeBatch()。

#2

First of all this you should know :

首先，你应该知道:

boolean execute() Executes the SQL statement in this PreparedStatement object, which may be any kind of SQL statement.

boolean execute()在这个PreparedStatement对象中执行SQL语句，该对象可以是任何类型的SQL语句。

ResultSet executeQuery() Executes the SQL query in this PreparedStatement object and returns the ResultSet object generated by the query.

ResultSet executeQuery()在这个PreparedStatement对象中执行SQL查询并返回查询生成的ResultSet对象。

int executeUpdate() Executes the SQL statement in this PreparedStatement object, which must be an SQL INSERT, UPDATE or DELETE statement; or an SQL statement that returns nothing, such as a DDL statement.

int executeUpdate()在这个PreparedStatement对象中执行SQL语句，它必须是SQL INSERT、UPDATE或DELETE语句;或者不返回任何内容的SQL语句，比如DDL语句。

        int i=stmt.executeUpdate();
        if(i>0)
        {
              System.out.println("success");
        }
              else
        {
             System.out.println("stuck somewhere");

        }

Try this and check it out whether insert is happening or not

试试这个，看看插入是否发生

#3

Try this, whether you want to know whether the data is inserted or not , if the record is inserted it return true or else false.

尝试此操作，无论您是否想知道数据是否被插入，如果插入记录，它将返回true或else false。

  if(action > 0){
      return true;
    }else{
      return false;
      }

#4

-1

If you don't get a exception I think query is went ok. Or, you might be able to use executeUpdate() (http://docs.oracle.com/javase/7/docs/api/java/sql/PreparedStatement.html#executeUpdate() )

如果你没有一个例外，我认为查询没问题。或者，您可以使用executeUpdate() (http://docs.oracle.com/javase/doc7/s/api/java/sql/preparedstatement.html #executeUpdate())

You can do a select count(*) do validate number of records if you want.

如果需要，可以执行select count(*)验证记录的数量。

#1