如何解决MySQLSyntaxErrorException
在我的项目中,我编写了一些代码从数据库表中搜索员工姓名,并将其加载到jcombobox中 表名:如何解决MySQLSyntaxErrorException,mysql,sql,swing,jcombobox,Mysql,Sql,Swing,Jcombobox,在我的项目中,我编写了一些代码从数据库表中搜索员工姓名,并将其加载到jcombobox中 表名:员工 列名:empid(Primarykey)、emp_名称、位置 通常我是这样编写搜索查询的 public void EmployeeName1(JComboBox comboName) { Vector v = new Vector(); try { ResultSet rs = db.getData("select emp_name from emplo
员工
列名:empid(Primarykey)、emp_名称、位置
通常我是这样编写搜索查询的
public void EmployeeName1(JComboBox comboName) {
Vector v = new Vector();
try {
ResultSet rs = db.getData("select emp_name from employee");
v.add("--SELECT--");
while (rs.next()) {
v.add(rs.getString("emp_name"));
comboName.setModel(new DefaultComboBoxModel(v));
}
} catch (Exception e) {
e.printStackTrace();
}
}
它工作得很好
但现在我对这段代码做了一些不同的解释。
但是当我运行这段代码时,我遇到了这个错误
com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: Table 'textile.tablename' doesn't exist
这是我的db类代码:
package Model;
//import static Model.JDBC.con;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.swing.JOptionPane;
public class JDBC {
static String driver = "com.mysql.jdbc.Driver";
static String url = "jdbc:mysql://localhost/textile";
static Connection con;
static boolean b;
public static void setCon() {
try {
Class.forName(driver);
con = DriverManager.getConnection(url, "root", "access456");
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
public static Connection getCon() throws Exception {
if (con == null) {
setCon();
}
return con;
}
public static boolean putData(String sql) {
try {
PreparedStatement state = getCon().prepareStatement(sql);
state.executeUpdate();
b = true;
} catch (Exception ex) {
b = false;
JOptionPane.showMessageDialog(null, ex);
}
return b;
}
public static ResultSet getData(String sql) throws Exception {
Statement state = JDBC.getCon().createStatement();
ResultSet rset = state.executeQuery(sql);
return rset;
}
}
在我看来,在这两个代码段之间,您保持了所有其他内容不变。我唯一能看到你应该改变的是:
ResultSet rs = db.getData("select columnName from tableName");
到
添加columnname和tablename作为变量并更改:
ResultSet rs = db.getData("select columnName from tableName");
到
ResultSet rs = db.getData("select " + columnName + " from " + tableName);
ResultSet rs = db.getData("select columnName from tableName");
ResultSet rs = db.getData("select "+columnName+" from "+tableName);