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SQL Query With Aggregates and Joins

MediumSQL · PostgreSQL00:00
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Your question is SQL Query With Aggregates and Joins. Start with the requirements and the four tables on the right.

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Problem

Write an SQL query based on aggregate functions, wildcard operators, and joins.

Use the provided school, student, registration, and exam tables. Include students whose last names begin with A% and exams whose titles begin with SAT%. Return only schools with at least two qualifying attempts.

Output

  1. One row per qualifying school with school_code, school_name, eligible_students, exam_attempts, average_score, highest_score, and performance_rank
  2. Rank schools by average score descending, then highest score descending
  3. Sort by performance_rank, then school_name

Schema

schools
ColumnTypeDescription
school_idPKINTUnique school identifier
school_codeVARCHAR(20)Short school code
school_nameVARCHAR(120)School name
students
ColumnTypeDescription
student_idPKINTUnique student identifier
school_idINTStudent's school
first_nameVARCHAR(60)Student first name
last_nameVARCHAR(60)Student last name
registrations
ColumnTypeDescription
registration_idPKINTUnique exam registration
student_idINTRegistered student
exam_idINTRegistered exam
scoreINTExam score
exams
ColumnTypeDescription
exam_idPKINTUnique exam identifier
exam_titleVARCHAR(100)Exam title
exam_yearINTExam administration year
Tablesschoolsstudentsregistrationsexams
Your solutionPostgreSQL
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