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SQL and Programming Interview Mix
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SQL and Programming Interview Mix

MediumSQL · PostgreSQL

Problem

How would you approach a round that mixes SQL questions, programming, and a behavioral interview?

For the SQL portion, write a PostgreSQL query that summarizes completed transaction activity for every user.

Output

  1. One row per user, including users with no transactions
  2. Columns: user_id, email, completed_transaction_count, completed_transaction_total, and activity_status
  3. Include only transactions whose status is completed; treat missing totals as zero
  4. Order by total descending, then user_id ascending

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
emailVARCHAR(255)User email address
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
user_idINTUser associated with the transaction
statusVARCHAR(30)Transaction processing status
amountDECIMAL(12,2)Transaction amount
Tablesuserstransactions
Interviewer

Your question is SQL and Programming Interview Mix. Start with the requirements and the two tables in the Question tab.

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