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Average Score SQL Query
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Average Score SQL Query

MediumSQL · PostgreSQL

Problem

How would you compute the average score by question using SQL?

Use the questions and responses tables. Include every question, ignore NULL scores when calculating averages, and preserve questions with no scored responses.

Output

  1. One row per question with question_id, question_text, and average_score
  2. Return NULL for questions without scored responses
  3. Order by question_id ascending

Schema

questions
ColumnTypeDescription
question_idPKINTUnique identifier for the question
question_textVARCHAR(255)Text displayed for the question
responses
ColumnTypeDescription
response_idPKINTUnique identifier for the response
question_idINTQuestion answered by the response
respondent_nameVARCHAR(100)Optional respondent name
scoreNUMERIC(4,2)Numeric score assigned to the response
Tablesquestionsresponses
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Your question is Average Score SQL Query. Start with the requirements and the two tables in the Question tab.

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