Create 596. Classes More Than 5 Students

SQL_50/596. Classes More Than 5 Students

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+Table: Courses
+
++-------------+---------+
+| Column Name | Type    |
++-------------+---------+
+| student     | varchar |
+| class       | varchar |
++-------------+---------+
+(student, class) is the primary key (combination of columns with unique values) for this table.
+Each row of this table indicates the name of a student and the class in which they are enrolled.
+
+
+Write a solution to find all the classes that have at least five students.
+
+Return the result table in any order.
+
+The result format is in the following example.
+
+
+
+Example 1:
+
+Input: 
+Courses table:
++---------+----------+
+| student | class    |
++---------+----------+
+| A       | Math     |
+| B       | English  |
+| C       | Math     |
+| D       | Biology  |
+| E       | Math     |
+| F       | Computer |
+| G       | Math     |
+| H       | Math     |
+| I       | Math     |
++---------+----------+
+Output: 
++---------+
+| class   |
++---------+
+| Math    |
++---------+
+Explanation: 
+- Math has 6 students, so we include it.
+- English has 1 student, so we do not include it.
+- Biology has 1 student, so we do not include it.
+- Computer has 1 student, so we do not include it.
+----------------------------------------------------------
+select class
+from Courses
+group by class
+having count(class)>=5;