Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to group by column name and ensure the query retrieves the last update in MySQL?
Let us first create a table −
mysql> create table DemoTable621 (UserName varchar(100),UserEmailId varchar(100),UserLastPost datetime); Query OK, 0 rows affected (0.59 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable621 values('John','John@gmail.com','2019-04-10 11:01:10');
Query OK, 1 row affected (0.47 sec)
mysql> insert into DemoTable621 values('John','John@gmail.com','2019-07-14 13:07:10');
Query OK, 1 row affected (0.15 sec)Display all records from the table using select statement −
mysql> select *from DemoTable621;
This will produce the following output −
+----------+----------------+---------------------+ | UserName | UserEmailId | UserLastPost | +----------+----------------+---------------------+ | John | John@gmail.com | 2019-04-10 11:01:10 | | John | John@gmail.com | 2019-07-14 13:07:10 | +----------+----------------+---------------------+ 2 rows in set (0.00 sec)
Following is the query to group by column name and ensure the query retrieves the last update −
mysql> select UserName,UserEmailId,max(UserLastPost) from DemoTable621 group by UserName,UserEmailId;
This will produce the following output −
+----------+----------------+---------------------+ | UserName | UserEmailId | max(UserLastPost) | +----------+----------------+---------------------+ | John | John@gmail.com | 2019-07-14 13:07:10 | +----------+----------------+---------------------+ 1 row in set (0.19 sec)
Updated on: 23-Aug-2019
56 Views
Advertisements