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SQL Certification Leaderboard
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SQL Certification Leaderboard

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the student with the most number of certifications.

Asked in the Tech 1 stage.

Output

  1. Return one row for the student with the highest certification count.
  2. Include the student identifier, student name, and certification count.
  3. If multiple students tie for the top count, return all of them.
  4. Sort by certification count descending, then student name ascending.

Schema

students
ColumnTypeDescription
student_idPKINTUnique identifier for the student
student_nameVARCHAR(255)Student full name
emailVARCHAR(255)Student email address
enrollment_dateDATEDate the student enrolled
certifications
ColumnTypeDescription
certification_idPKINTUnique identifier for the certification record
student_idINTReferences the student who earned the certification
certification_nameVARCHAR(255)Name of the certification
earned_dateDATEDate the certification was earned
Tablesstudentscertifications
Interviewer

Your question is SQL Certification Leaderboard. Start with the requirements and the two tables in the Question tab.

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