Get RETURNING value from Postgresql via Java

问题

From Java, I'm calling a prepared statement in Postgresql with an insert that has a RETURNING clause for my identity column. In PG admin it comes right back, but not sure how to get it from my prepared statement:

        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();

回答1:

According to the javadoc, PreparedStatement inherits from Statement and the latter contains a getResultSet() method. In other words, try this:

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);

Leave a comment if you have further issues.

回答2:

I do not have enough reputation to Comment and my Edit got rejected, so sorry for re-posting the already accepted answer from hd1.

executeUpdate expects no returns; use execute. Check if there is some results before trying to retrieve the value.

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.execute();
ResultSet last_updated_person = stmt.getResultSet();
if(last_updated_person.next()) {
   int last_updated_person_id = last_updated_person.getInt(1);
}

回答3:

Calling executeUpdate() expects no result from statement. Call stmt.execute() and then stmt.getResultSet()

来源：https://stackoverflow.com/questions/23691715/get-returning-value-from-postgresql-via-java

标签

java

prepared-statement