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LEFT JOIN for Missing Records
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LEFT JOIN for Missing Records

EasySQL · PostgreSQL

Problem

Write a SQL query using a LEFT JOIN to identify records in a Students table that do not have corresponding entries in a Marks table.

Return each student without any marks record, including students whose IDs do not appear in Marks.

Output

  1. One row per unmatched student
  2. Columns: student_id, student_name
  3. Sort by student_id in ascending order

Schema

students
ColumnTypeDescription
student_idPKINTUnique identifier for the student
student_nameVARCHAR(100)Student's full name
grade_levelINTStudent's grade level
marks
ColumnTypeDescription
mark_idPKINTUnique identifier for the marks record
student_idINTStudent associated with the marks record
subjectVARCHAR(50)Subject for the recorded mark
scoreNUMERIC(5,2)Numerical score for the subject
Tablesstudentsmarks
Interviewer

Your question is LEFT JOIN for Missing Records. Start with the requirements and the two tables in the Question tab.

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CodePostgreSQL
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