通过Java从Postgresql获取RETURNING值

Question

从Java，我正在Postgresql中使用带有对我的身分列的RETURNING子句的插入来调用准备好的语句。在PG管理员中，它马上回来，但不确定如何从准备好的语句中获取它：

        String insertStatement = "INSERT INTO person(\n" +
                "            name, address, phone, customer_type, \n" +
                "            start_dtm)\n" +
                "    VALUES (?, ?, ?, ?, \n" +
                "            ?)\n" +
                "    RETURNING person_id;";


        PreparedStatement stmt = connection.prepareStatement(insertStatement);

        stmt.setObject(1, perToSave.getName(null));
        stmt.setObject(2, editToSave.getAddress());
        stmt.setObject(3, editToSave.getPhone());
        stmt.setObject(4, editToSave.getCustType());
        long epochTime = java.lang.System.currentTimeMillis();
        stmt.setObject(5, new java.sql.Date(epochTime));

        stmt.executeUpdate();

Answer 1

根据javadoc，PreparedStatement继承自Statement，后者包含getResultSet（）方法。换句话说，请尝试以下操作：

String insertStatement = "INSERT INTO person(\n" +
                "            name, address, phone, customer_type, \n" +
                "            start_dtm)\n" +
                "    VALUES (?, ?, ?, ?, \n" +
                "            ?)\n" +
                "    RETURNING person_id;";


PreparedStatement stmt = connection.prepareStatement(insertStatement);

stmt.setObject(1, perToSave.getName(null));
stmt.setObject(2, editToSave.getAddress());
stmt.setObject(3, editToSave.getPhone());
stmt.setObject(4, editToSave.getCustType());
long epochTime = java.lang.System.currentTimeMillis();
stmt.setObject(5, new java.sql.Date(epochTime));

stmt.executeUpdate();
ResultSet last_updated_person = stmt.getResultSet();
last_updated_person.next();
int last_updated_person_id = last_updated_person.getInt(1);

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