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Find Duplicate Rows Query

EasySQL · PostgreSQL00:00
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Your question is Find Duplicate Rows Query. Start with the requirements and the one table on the right.

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Problem

Dover India’s Asset Registry contains imported equipment records from multiple operational systems. Some records may have been loaded more than once, so the data team needs to identify duplicate business records.

Write a PostgreSQL query that identifies duplicate rows based on employee_code, email, department, and work_location. Treat record_id as a unique technical identifier and do not use it when determining duplicates.

Requirements

  1. Group records by all business columns listed above and return only groups containing more than one row.
  2. Return the duplicated business values and the number of occurrences, ordered by duplicate_count descending and then employee_code ascending.

Schema

dover_asset_registry
ColumnTypeDescription
record_idPKINTEGERUnique technical record identifier
employee_codeVARCHAR(20)Employee or asset owner code
emailVARCHAR(150)Registered contact email
departmentVARCHAR(80)Dover India department
work_locationVARCHAR(80)Assigned work location
Tablesdover_asset_registry
Your solutionPostgreSQL
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