我正在创建一个JavaFX独立应用程序并使用嵌入式derby数据库并通过JDBC连接到它。问题在于，每当我尝试与数据库表进行交互时，我都会得到＆＃34; java.sql.SQLSyntaxErrorException：Table / View＆＃39; BUILDINGS＆＃39;不存在。＆＃34;。
我搜索了很多，但我无法解决它。我查了提到here的三个原因，但我仍然得到同样的错误。 This帖子听起来与我的情况非常相似，但我无法弄清楚他是如何解决的。我已经从连接元数据和netbeans服务选项卡检查了数据库URL，但它是一样的。
以下是与问题相关的代码段：
public class DataBaseUtility {
public Connection derbyDBConnection(String url){
Connection con = null;
String driver = "org.apache.derby.jdbc.EmbeddedDriver";
try {
Class.forName(driver).newInstance();
con = DriverManager.getConnection(url, "", "");
con.setSchema("APP");
} catch (ClassNotFoundException | SQLException |
InstantiationException | IllegalAccessException ex) {
Logger.getLogger(DataBaseUtility.class.getName())
.log(Level.SEVERE, null, ex);
}
return con;
}
public ResultSet databaseQuerying(Connection con, String query){
ResultSet resultSet = null;
try {
PreparedStatement preStmt = con.prepareStatement(query);
resultSet = preStmt.executeQuery();
} catch (SQLException ex) {
Logger.getLogger(DataBaseUtility.class.getName()).log(Level.SEVERE, null, ex);
}
return resultSet;
}}
和
public class MainApp extends Application {
public static DataBaseUtility dbUtility ;
public static Connection con;
@Override
public void init(){
dbUtility = new DataBaseUtility();
con = dbUtility.derbyDBConnection("jdbc:derby:elsarhEmbedded");
try {
DatabaseMetaData dbmd = con.getMetaData();
System.out.println("\n----------------------------------------------------") ;
System.out.println("Database Name = " + dbmd.getDatabaseProductName()) ;
System.out.println("Database User Name= " + dbmd.getUserName()) ;
System.out.println("Database Version = " + dbmd.getDatabaseProductVersion()) ;
System.out.println("Driver Name = " + dbmd.getDriverName()) ;
System.out.println("Driver Version = " + dbmd.getDriverVersion()) ;
System.out.println("Database URL = " + dbmd.getURL()) ;
System.out.println("----------------------------------------------------") ;
/*
-------------the result from the above ----------
Database Name = Apache Derby
Database User Name= APP
Database Version = 10.14.1.0 - (1808820)
Driver Name = Apache Derby Embedded JDBC Driver
Driver Version = 10.14.1.0 - (1808820)
Database URL = jdbc:derby:elsarhEmbedded
*/
} catch (SQLException ex) {
Logger.getLogger(MainApp.class.getName()).log(Level.SEVERE, null, ex);
}
}
我试图从netbeans向数据库执行命令并将数据插入到同一个表中并且它可以工作。