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Course IDs With >100 Students

EasySQL · PostgreSQL00:00
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Your question is Course IDs With >100 Students. Start with the requirements and the two tables on the right.

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Problem

Antra's learning platform needs to identify courses whose total registrations exceed 100 students. The registration data is stored in batches, where each batch represents a distinct group of students for a course and term.

Write a PostgreSQL query that returns every qualifying course's name and ID.

Requirements

  1. Join courses to course_registration_batches using the course ID.
  2. Sum the registered students across all batches for each course.
  3. Return only courses with more than 100 registered students.
  4. Sort the output by course_id in ascending order.

Schema

courses
ColumnTypeDescription
course_idPKINTUnique identifier for the course
course_nameVARCHAR(150)Name of the Antra course
course_registration_batches
ColumnTypeDescription
batch_idPKINTUnique identifier for a registration batch
course_idINTCourse associated with the registration batch
termVARCHAR(30)Academic term for the registration batch
registered_countINTNumber of distinct students registered in the batch
Tablescoursescourse_registration_batches
Your solutionPostgreSQL
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