Select record having most recent date

Question

Table: Order
Code     ImportId     EntryDate
1 100
10/11/2014
1 101
10/14/2014
1 102
10/10/2014
2  103  10/11/2014
2   104  10/15/2014
I want to select the record having the most recent EntryDate grouped by Code. In the select, i need to return the ImportId.
Anonymous

Answer 1

Please post DDL, so that people do not have to guess what the keys, constraints, Declarative Referential Integrity, data types, etc. in your schema are. Learn how to follow ISO-11179 data element naming conventions and formatting rules. Nothing you posted
was right. Temporal data should use ISO-8601 formats. This is the only format allowed in the ANSI-ISO SQL Standards and it is the most common IT standard on Earth; but you do not know it! 
Code should be in Standard SQL as much as possible and not local dialect. There is no such crap as a generic “code” in RDBMS. Table have keys, so you have no table! Rows are not records; this is a basic concept. 
This is minimal polite behavior on SQL forums. Here is my guess at what a polite, competent person might have posted. 
CREATE TABLE Import_Orders
(order_type INTEGER NOT NULL
 CHECK(order_type IN (1,2)),
 import_id CHAR(3) NOT NULL PRIMARY KEY, 
 entry_date DATE NOT NULL);
INSERT INTO Import_Orders
VALUES
(1, 100, '2014-10-11'),
(1, 101, '2014-10-14'),
(1, 102, '2014-10-10'),
(2, 103, '2014-10-11'),
(2, 104, '2014-10-15');
I want to select the record [sic] having the most recent entry_date grouped by order_type. In the select, I need to return the import_id.
If you return only the import_id, then the most recent entry_date does not matter! Think about it! Did you want the whole row with the most recent entry_date? Here is a common idiom. 
WITH X (import_id, order_type, entry_date, entry_date_max)
AS
(SELECT import_id, order_type, entry_date, 
        MAX(entry_date) OVER (PARTITION BY order_type)
   FROM Import_Orders) 
SELECT import_id, order_type, entry_date
  FROM X
 WHERE entry_date = entry_date_max;
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