从表中仅选择日期时间值最高的一行

Question

I have a table that looks similar to this:

images
    image_id       int
    user_id        int
    datetime       datetime

So, I need to get only one result. This result should have a specific user_id and should only be the most recent row in the table.

I've checked out many similar questions, but wasn't able to understand how to do it and the codes I found didn't work at all.

How can I achieve this?

Here's a start query:

SELECT *
FROM image
WHERE user_id = :user_id 

How do I change this query to select only the most recent row with a specific user_id?

Answer 1

You can use order by clause like this:

SELECT *
FROM image
WHERE user_id = :user_id ORDER BY datetime DESC LIMIT 1

Answer 2

For SQL Server you can use:

SELECT TOP(1) *
FROM image
WHERE user_id = :user_id 
ORDER BY datetime DESC

Answer 3

For MySQL try the following:

SELECT * FROM image
WHERE user_id = :user_id
ORDER BY datetime DESC limit 1

limit will work with MySQL

For further info on MySql statements look here: http://dev.mysql.com/doc/refman/5.0/en/sql-syntax.html

Answer 4

Select * from images where User_id = :User_id Order by datetime DESC Limit 1

Hope it works :)

Answer 5

通过使用限制，您可以获得所需数据的数量

limit required_no.