我只是想在我的应用程序中使用更新,但我不能。控制台,这个 mysql 命令有效,但在这里,没有。
好吧,我在我的程序中使用它:
conexao = poolMySQL.connect();
final String sql = "UPDATE professor SET codlocal = ? WHERE codprof = ?";
pstmt = conexao.prepareStatement(sql);
pstmt.setInt(1, local);
pstmt.setInt(2, id);
try {
pstmt.executeUpdate(sql);
} catch (SQLException ex) {
Logger.getLogger(ProfessorDAO.class.getName()).log(Level.SEVERE, null, ex);
}
提醒一下,codlocal 是来自另一个名为 Localidade 的表的外键。我看到了一些关于加入的例子,但我无法想象这对我有什么用。
我明白了:
Grave: null
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 '? WHERE codprof = ?' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.Util.getInstance(Util.java:384)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3566)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3498)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1959)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2113)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2562)
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1664)
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1583)
at DAO.ProfessorDAO.atualizaLocalidade(ProfessorDAO.java:153)
at DAO.Main.main(Main.java:23)
那么,我能做些什么呢?