Get the maximum exam date using a user-defined variable in SQL

To get the maximum exam date with a user-defined variable, the code is as follows −

select date(max(yourColumnName )) into @yourVariableName  from yourTableName;

To understand the above syntax, let us first create a table −

mysql> create table DemoTable2001
(
   ExamDate date
);
Query OK, 0 rows affected (0.60 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable2001 values('2019-01-10');
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable2001 values('2018-12-31');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable2001 values('2018-11-18');
Query OK, 1 row affected (0.39 sec)
mysql> insert into DemoTable2001 values('2019-07-25');
Query OK, 1 row affected (0.13 sec)

Display all records from the table using select statement −

mysql> select * from DemoTable2001;

This will produce the following output −

+------------+
| ExamDate   |
+------------+
| 2019-01-10 |
| 2018-12-31 |
| 2018-11-18 |
| 2019-07-25 |
+------------+
4 rows in set (0.00 sec)

Here is the query to get the maximum date. We will first create a user-defined variable −

mysql> set @comingExamDate:=null;
Query OK, 0 rows affected (0.00 sec)
mysql> select date(max(ExamDate)) into @comingExamDate from DemoTable2001;
Query OK, 1 row affected (0.00 sec)
mysql> select @comingExamDate;

This will produce the following output −

+------------------+
| @commingExamDate |
+------------------+
| 2019-07-25       |
+------------------+
1 row in set (0.00 sec)