Question

表雇主

CREATE TABLE "Employer" ("employerID" INTEGER PRIMARY KEY  NOT NULL ,
"name" CHAR,
"industry" CHAR,
"contact1" CHAR,
"contact2" CHAR,
"email" CHAR,
"website" CHAR,
"facts" CHAR,
"phone" VACHAR)

表格工作

CREATE TABLE "Job" ("jobID" INTEGER PRIMARY KEY  NOT NULL ,
"employerID" INTEGER,
"title" CHAR,
"description" CHAR,
"type" CHAR,"salary" CHAR,
"benefits" CHAR,
"vacancies" INTEGER,
"closing" CHAR,
"requirement" CHAR,
"placement" BOOL,
"applyTo" CHAR,
"status" CHAR,
"posted" CHAR, 
"location" CHAR)

 try {  
    //String sqlStm = "INSERT INTO Job (employerID,title,description,type,salary,benefits,vacancies,closing,requirement,placement,applyTo,status,posted,location) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?) INNER JOIN Employer ON Job.employerID = Employer.employerID"; 
   String sqlStm = "SET @SELECTED_ID = (SELECT employerID FROM Employer WHERE name = '"+comboEmployer.getSelectedItem().toString()+"') INSERT INTO Job (employerID,title,description,type,salary,benefits,vacancies,closing,requirement,placement,applyTo,status,posted,location)VALUES (@SELECTED_ID,?,?,?,?,?,?,?,?,?,?,?,?,?)";
       pst = conn.prepareStatement(sqlStm);

    pst.setString(2,txtTitle.getText());
     pst.setString(3,areaDescription.getText());
      pst.setString(4,comboType.getSelectedItem().toString());
       pst.setString(5,txtSalary.getText());
        pst.setString(6,areaBenefits.getText());
         pst.setString(7,txtVac.getText());
          pst.setString(8,txtDate.getDateFormatString().toString());
           pst.setString(9,areaReq.getText());
            pst.setString(10,comboPlace.getSelectedItem().toString());
             pst.setString(11,txtWeb.getText());
              pst.setString(12,comboStatus.getSelectedItem().toString());
               pst.setString(13,"01-01-2013");
                pst.setString(14,txtLoc.getText());
                   pst.executeUpdate();
   } catch (Exception e) {
        JOptionPane.showMessageDialog(null,e);
    } finally {
        try {
            rs.close();
            pst.close();
        } catch (Exception e) {
        }
    }  
}

我正在尝试允许用户向系统添加作业，而表单要求他们从Employer表中选择雇主。我不确定如何将所选择的雇主与JCombobox联系起来。即Job表中的employerID应与employer表的employerID匹配。我设法做了Select声明，

 sql = "SELECT Job.jobID as 'Job ID', Employer.name as'Company', Job.title as 'Role', Job.type as 'Type', Job.closing as 'Closing Date' FROM Job INNER JOIN Employer ON Job.employerID=Employer.employerID ORDER BY Employer.name";

但不确定如何INSERT进入sqlite manager。下面是表格： enter image description here

Answer 1

您可以从前端编码本身处理它。 Combobox有两件事 - 值和文本。 ComboBox项的值应为Job id，文本应为Description。使用Select查询检索此部分。然后，您可以插入Selected选项的值。因此将插入作业ID。

Answer 2

我想我明白你要做什么。您正尝试使用表单上输入的值添加到“作业”表。由于雇主的下拉框采用文本形式，而“雇主”表仅接受雇主ID，因此您希望将雇主姓名翻译为雇主ID。

尝试使用此代码。它是用vanilla SQL编写的，因此您可能需要对SQLite进行一些小的调整

SET @SELECTED_ID = (SELECT employerID
                   FROM Employer
                   WHERE name = @your_text_box_variable)

INSERT INTO Job (employerID,title,description,type,salary,benefits,vacancies,closing,requirement,placement,applyTo,status,posted,location) 
VALUES (@SELECTED_ID,?,?,?,?,?,?,?,?,?,?,?,?,?)

基本上，我们从表单中获取雇主姓名的值（使用变量@your_text_box_variable传输）并撤回与该名称相关联的雇主ID。然后，我们可以使用此雇主ID插入“工作”表。

Answer 3

您的JComboBox应包含Employer类型的对象。该雇主类应该至少包含雇主的ID（能够唯一地识别他）和雇主的姓名（在组合框中显示）。

要插入新作业，只需从组合框中获取选定的雇主，获取其ID，然后将其传递给您的查询（不应该有任何内部联接）：

insert into job (employerID,title, ...) values (?, ?, ...)

插入在Java中使用INNER JOIN

3 个答案: