UCanAccess Java 执行错误

Question

尝试使用以下代码从 MS Access 数据库获取详细信息时：

//returns the details of a specific employee for use in the update GUI
public static String getEmployeeDetails(int empID) throws SQLException{
    String employee = "";
    Statement stmt = conn.createStatement();
    String query = "SELECT employeetbl.Department, "
            + "employeetbl.Surname, "
            + "employeetbl.FirstName, "
            + "employeetbl.CurrentPosition, "
            + "FORMAT(employeetbl.DateOfBirth, 'yyyy/mm/dd') AS DateOfBirth, "
            + "employeetbl.TotalYearsRelevantExperience, "
            + "employeetbl.HighestQualification, "
            + "employeetbl.EmailAddress, "
            + "employeetbl.PhoneNo, "
            + "FORMAT(employeetbl.DateOfEmployment, 'yyyy/mm/dd') AS DateOfEmployment "
            + "FROM employeetbl WHERE EmployeeID = "+empID+";";
    ResultSet rs = stmt.executeQuery(query);
    while(rs.next()){
        employee = rs.getString("Department")
                +"#"+rs.getString("Surname")
                +"#"+rs.getString("FirstName")
                +"#"+rs.getString("CurrentPosition")
                +"#"+rs.getString("DateOfBirth")
                +"#"+rs.getString("TotalYearsRelevantExperience")
                +"#"+rs.getString("HighestQualification")
                +"#"+rs.getString("EmailAddress")
                +"#"+rs.getString("PhoneNo")
                +"#"+rs.getString("DateOfEmployment");
    }
    return employee;
}

从此方法调用：

if(cmbTable.getSelectedItem().equals("Employees")){
            String[] tmp = cmbRecord.getSelectedItem().toString().split("-");
            int empID = Integer.parseInt(tmp[0]);
            String employeeDetails = Master.getEmployeeDetails(empID);
            String[] employee = employeeDetails.split("#");
            cmbDepartment.setSelectedItem(employee[0]);
            txtSurname.setText(employee[1]);
            txtFirstName.setText(employee[2]);
            txtCurrentPos.setText(employee[3]);
            txtDOB.setText(employee[4]);
            txtExperience.setText(employee[5]);
            txtQualification.setText(employee[6]);
            txtEmail.setText(employee[7]);
            txtPhone.setText(employee[8]);
            txtEmployment.setText(employee[9]);
        }

我遇到了以下错误

error: net.ucanaccess.jdbc.UcanaccessSQLException: UCAExc:::3.0.0 Java execution: FORMAT

我不知道是什么导致了这个错误，因为 SQL 在 Access 中执行时工作得很好并且需要格式，否则它会输出记录信息，包括未设置或使用的时间。

Answer 1

我会从您的 SQL 字符串中删除 FORMAT 并将日期格式化为 Java。我不知道返回的日期格式是什么，但这应该允许您解析它，然后在 Calendar.set() 方法中输入字段，如下所示：

public static void main(String[] args) {
    final Calendar calendar = Calendar.getInstance();
    calendar.set(2015, Calendar.AUGUST, 21, 9, 27);
    final Date date = calendar.getTime();
    final String formattedDate = new SimpleDateFormat("yyyy/MM/dd").format(date);
    System.out.println("formattedDate = " + formattedDate);
}

Answer 2

对于未来的读者：格式化功能是在ucanaccess中实现的，并且最初发布的代码是正确的。所以下面的代码在 ucanaccess 上运行良好：

select format(#2001-03-02#, 'yyyy/mm/dd') from dual.

然而，缺少空参数的处理，这很可能是导致问题的原因。所以 select format(null, 'yyyy/mm/dd') from dual; 导致抛出异常。即使我解决了这个问题，也需要使用特定的 hsqldb 语法将空值转换为时间戳，因为函数 FORMAT(varchar,varchar) 和 FORMAT(double,varchar)。所以我建议这个（简化的）解决方法：

select nvl2(employeetbl.DateOfBirth,FORMAT(employeetbl.DateOfBirth, 'yyyy/mm/dd'),null) AS DateOfBirth from ...

请注意，与 access 一样，mm 表示月（而不是分钟）。

UCanAccess Java 执行错误

UCanAccess Java Execution Error

java

ms-access

ucanaccess