获取MYSQL中重复条目的最新数据

Question

I have a mysql table that contains all the subscribed plan by users. I am trying to create a SELECT statement that will allow me to select for a particular user from the table. Also, if that user have duplicated entries, it will get the latest date of all.

For example, I want to look for John from the table and the date I should get is 2015-09-10.

Subscribed table
ID   FirstName   Date
-------------------------------
1   John        2015-05-30
2   Mary        2014-01-10
3   John        2015-09-10
4   John        2015-03-15
5   Loen        2013-12-11

How should I go about creating the SELECT statement to above the result?

Answer 1

If you just need the first one, you can use LIMIT in conjunction with ORDER BY:

SELECT * FROM `Subscribed`
  WHERE `FirstName` = 'John' -- Get the name John.
  ORDER BY `Date` DESC       -- Sort results in descending order by Date.
  LIMIT 1                    -- Limit the results to one.

The result will be ordered by date in descending order, and the LIMIT 1 gives out the first row.

Or to be precise, you can also use Grouping Functions if you need more than one row.

SELECT `FirstName`, MAX(`Date`) FROM `Subscribed`
  WHERE `FirstName` = 'John'
  GROUP BY `FirstName`

Fiddle: http://www.sqlfiddle.com/#!9/ebb90/1