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Validate Data Integrity

MediumSQL · PostgreSQL00:00
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Your question is Validate Data Integrity. Start with the requirements and the two tables on the right.

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Problem

What steps would you take to ensure the integrity of your data before analysis?

Use the users and transactions tables to identify transaction records with missing user references, invalid amounts, unsupported or missing statuses, invalid dates, or users whose email appears more than once.

Output

  1. One row per transaction, with transaction_id, integrity_status, and issue_details.
  2. Mark rows as valid only when no listed issue exists; otherwise mark them as invalid.
  3. Order by transaction_id ascending.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
full_nameVARCHAR(100)User's full name
emailVARCHAR(255)User email address
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
user_idINTReferenced user identifier
amountNUMERIC(12,2)Transaction amount
statusVARCHAR(20)Transaction status
transaction_dateDATETransaction date
Tablesuserstransactions
Your solutionPostgreSQL
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