获取 MySQL 表中的最后一个条目

Question

I'm basically trying to make a "goal" bar. The goal is determined by getting the last entry I made in a MySQL table. I want to get the ID of the last entry therefore.

How do I get the last entry in the table and then get the id from that last entry?

(Using PHP)

Answer 1

To get the greatest id:

SELECT MAX(id) FROM mytable

Then to get the row:

SELECT * FROM mytable WHERE id = ???

Or, you could do it all in one query:

SELECT * FROM mytable ORDER BY id DESC LIMIT 1

Answer 2

you can use LAST_INSERT_ID() function. example:

$sql = "SELECT * FROM mytable WHERE id = LAST_INSERT_ID()";

Answer 3

您可以使用此查询来获取您希望使用此示例中使用的SQL查询所需的结果：

$sql = "SELECT user_id FROM my_users_table ORDER BY user_id DESC LIMIT 0,1";

Answer 4

如果该字段是自动递增的，那么您可以使用LAST_INSERT_ID

Answer 5

To do this reliably, you must have some field in the table that you can examine to determine which is last. This could be a time stamp of when you added the record, a sequence number that continually increases (especially an auto-incrementing sequence number), etc.

Then, let's suppose it's a sequence number called "rec_seq". You'd write something like:

select * from my_table
where rec_seq=(select max(rec_seq) from my_table)

Answer 6

以相反的顺序从表中选择所有字段并设置限制0,1这将为您提供表字段数据的最后结果

Answer 7

获取用户的最新条目

'SELECT user_id FROM table_name WHERE user_id = '.$userid.' ORDER BY user_id DESC LIMIT 1';

Answer 8

The above answers show how to get the latest entry by id. If one uses non-incrementing ids such as UUIDs as keys, this does not work. In that case one could use a created_at column instead.

-- highest id
SELECT * FROM some_table ORDER BY id DESC LIMIT 1;

-- latest created at date
SELECT * FROM some_table ORDER BY created_at DESC LIMIT 1;