find the median in sql

1# FOR TABLES WITH ODD NUMBER OF ROWS
2
3# For column1 in table1 with 'n' number of rows. Where 'n' is an odd number.
4# 1. Change all column1 and table1 to your column and table name.
5# 2. Calculate (n/2)+0.5, where n=number of rows, and set it as LIMIT for t1.
6
7SELECT *
8FROM (SELECT column1
9      FROM table1
10      ORDER BY column1
11      LIMIT (n/2)+0.5) AS t1
12ORDER BY column1 DESC
13LIMIT 1;

1# FOR TABLES WITH EVEN NUMBER OF ROWS
2
3# For column1 in table1 with 'n' number of rows. Where 'n' is an even number.
4# 1. Change all column1 and table1 to your column and table name.
5# 2. Calculate (n/2)+1, where n=number of rows, and set it as LIMIT for t1.
6
7SELECT AVG(t2.column1)
8FROM (SELECT *
9	FROM (SELECT column1
10      	FROM table1
11     	 ORDER BY column1
12     	 LIMIT (n/2)+1) AS t1
13	ORDER BY column1 DESC
14	LIMIT 2) AS t2;

1SET @rowindex := -1;
2 
3SELECT
4   AVG(g.grade)
5FROM
6   (SELECT @rowindex:=@rowindex + 1 AS rowindex,
7           grades.grade AS grade
8    FROM grades
9    ORDER BY grades.grade) AS g
10WHERE
11g.rowindex IN (FLOOR(@rowindex / 2) , CEIL(@rowindex / 2));
12