我已经使用预备语句尝试了几次,但是它返回SQL异常。这是我的代码:
public ArrayList<String> name(String mobile, String password) { ArrayList<String> getdata = new ArrayList<String>(); PreparedStatement stmt = null; try { String login = "select mobile, password from tbl_1 join tbl_2 on tbl_1.fk_id=2.Pk_ID where mobile=? and password=?"; String data = "select * from tbl_2 where password='" + password + "'"; PreparedStatement preparedStatement = conn.prepareStatement(login); preparedStatement.setString(1, mobile); preparedStatement.setString(1, password); ResultSet rs = preparedStatement.executeQuery(login); Statement stmts = (Statement) conn.createStatement(); if (rs.next()) { System.out.println("Db inside RS"); ResultSet data = stmts.executeQuery(data); while (data.next()) { /* looping through the resultset */ getdata.add(data.getString("name")); getdata.add(data.getString("place")); getdata.add(data.getString("age")); getdata.add(data.getString("job")); } } } catch (Exception e) { System.out.println(e); } return getdata; }
运行此程序时,出现以下SQL异常:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '? and password=?' at line 1.
有什么建议可以使这项工作吗?任何代码都值得赞赏。
您需要使用:
preparedStatement.executeQuery();
代替
preparedStatement.executeQuery(login);
当您将字符串传递给executeQuery() 该 查询时?,将按字面意义执行查询,因此将其发送到数据库,然后数据库会产生错误。通过传递查询字符串,您不会执行传递值的“已缓存”准备语句。
executeQuery()
?