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How to query the last record through mysql

May 09, 2018 am 09:23 AM
mysqlphpInquire

Mysql query for the last record is rarely used in PHP. This article will explain its related operations in detail.

Recommended related mysql video tutorials: "mysql tutorial"

First, determine what the last item is.
Is the one with the latest editing time the last one, or the one with the largest number in a certain field but not the last one.
For example, if the maximum time is the last one, then all the data that meet the conditions will be filtered out, then sorted by time, and then get another piece of data.
SQL is as follows:

select a,b from table where a>'某个时间' order by a desc limit 11

(a in the above SQL is time).

Use max(time) to query! !

select oid,status,max(time) time from 表名 group by oid,max(time);SELECT * from tb where id = (SELECT max(id) FROM tb);12

mysql group to get the latest record (whole record)

mysql to get the latest record after grouping, the following two methods. One is to first filter out the largest and latest time , Query in the connected table. One is to sort first, and then query by group (the first one by default), which is the latest piece of data

select * from t_assistant_article as a, (select max(base_id) as base_id, max(create_time) as create_time from t_assistant_article as b group by base_id ) as b where a.base_id=b.base_id and a.create_time = b.create_time  
select base_id,max(create_time), max(article_id) as article_id from t_assistant_article as b group by base_id   
select * from (select * from t_assistant_article order by create_time desc) as a group by base_id  12345

mysql Query the row to row record to query the last row Query the first few rows and the next few rows of records with the first row of records
1. Query the first row of records:

select   *   from   table  limit   11

2. Query the nth to mth rows of records

select * from table1  limit n-1,m-n;SELECT * FROM table LIMIT 5,10;返回第6行到第15行的记录select * from employee limit 3,1; // 返回第4行123

3. Query the first n rows of records

select * from table1 limit 0,n;或select * from table1 limit n;123

4. Query the next n rows of records

select * from table1 order by id desc dlimit n;//倒序排序,取前n行 id为自增形式1

5. Query the next record of a record ($id)

select * from table1 where id>$id  order by id asc dlimit 11

6. Query the previous record of a record ($id)

select * from table1 where id<$id  order by id desc dlimit 1

This article provides a detailed explanation of the last record of mysql query. For more learning materials, please pay attention to the php Chinese website.

Related recommendations:

sql server finds the maximum value, minimum value, maximum value corresponding time, and minimum value corresponding time

Related explanations about left join on and where condition placement

Related knowledge about php mysql fuzzy query function

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