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Duplicate Credit Applications
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Duplicate Credit Applications

MediumSQL · PostgreSQL

Problem

Write a query utilizing window functions like ROW_NUMBER() or DENSE_RANK() to identify duplicate credit applications submitted within the same hour for CRIF.

Use applicant_id and product_type to define a duplicate group. Exclude records without a submission timestamp.

Output

  1. One row per application belonging to a duplicate group
  2. Include application_id, applicant_id, product_type, application_hour, duplicate_count, and duplicate_sequence
  3. Order by applicant, hour, submission timestamp, and application ID

Schema

credit_applications
ColumnTypeDescription
application_idPKINTUnique credit application identifier
applicant_idVARCHAR(20)CRIF applicant identifier
product_typeVARCHAR(30)Credit product requested
submitted_atTIMESTAMPApplication submission timestamp
Tablescredit_applications
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