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SQL Join on Shared Key
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SQL Join on Shared Key

EasySQL · PostgreSQL

Problem

What SQL query would you use to combine two tables and return only matching rows based on a shared key?

Write a PostgreSQL query using the provided tables. Return one row for each matching pair of records.

Output

  1. Columns: person_code, person_name, assignment_id, and assignment_status
  2. Include only rows with a shared non-null person_code
  3. Order by person_code, then assignment_id ascending

Schema

people
ColumnTypeDescription
person_idPKINTUnique identifier for the person
person_codeVARCHAR(20)Code used to match a person to an assignment
person_nameVARCHAR(100)Person's full name
assignments
ColumnTypeDescription
assignment_idPKINTUnique identifier for the assignment
person_codeVARCHAR(20)Code used to match an assignment to a person
assignment_statusVARCHAR(30)Current status of the assignment
Tablespeopleassignments
Interviewer

Your question is SQL Join on Shared Key. Start with the requirements and the two tables in the Question tab.

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