Getting the maximum value from a varchar field in MySQL
Use MAX() function along with SUBSTRING() for this. Let us first create a table −
mysql> create table DemoTable
-> (
-> Id varchar(200)
-> );
Query OK, 0 rows affected (0.52 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable values('2019-0515-1980');
Query OK, 1 row affected (0.49 sec)
mysql> insert into DemoTable values('2019-0516-780');
Query OK, 1 row affected (0.19 sec)
mysql> insert into DemoTable values('2019-0517-2780');
Query OK, 1 row affected (0.16 sec)Display all records from the table using select statement −
mysql> select *from DemoTable;
Output
+----------------+
| Id |
+----------------+
| 2019-0515-1980 |
| 2019-0516-780 |
| 2019-0517-2780 |
+----------------+
3 rows in set (0.00 sec)
Following is the query to get the maximum value from a varchar field −
mysql> select max(Id) from DemoTable
-> where Id LIKE CONCAT(SUBSTRING(Id, 1, 4),'%');
Output
+----------------+
| max(Id) |
+----------------+
| 2019-0517-2780 |
+----------------+
1 row in set (0.00 sec)
Published on 10-Jul-2019 15:31:47
