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Remove Duplicate Records
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Remove Duplicate Records

EasySQL · PostgreSQL

Problem

Write an SQL query to remove duplicate records.

Return the deduplicated records based on the business columns, excluding the surrogate record identifier. The result should contain each unique combination only once.

Output

  1. One row per unique combination of customer_email, full_name, and department
  2. Columns: customer_email, full_name, department
  3. Sort by customer_email, then full_name, then department in ascending order, with NULL values last

Schema

employee_directory
ColumnTypeDescription
record_idPKINTUnique identifier for the stored record
customer_emailVARCHAR(255)Business email associated with the record
full_nameVARCHAR(150)Full name associated with the record
departmentVARCHAR(100)Department associated with the record
Tablesemployee_directory
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