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Finding Duplicate Records

EasySQL · PostgreSQL00:00
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Your question is Finding Duplicate Records. Start with the requirements and the one table on the right.

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Problem

Bismart's customer master table may contain repeated email addresses from multiple imports. Write a SQL query to identify duplicate email values in the customers table.

Requirements

  1. Return each email that appears more than once.
  2. Include the number of rows for each duplicate email.
  3. Sort the result by duplicate count descending, then by email ascending.

Schema

customers
ColumnTypeDescription
customer_idPKINTPrimary key for each customer record
full_nameVARCHAR(100)Customer name
emailVARCHAR(255)Customer email address, may contain duplicates or NULL
created_atDATERecord creation date
Tablescustomers
Your solutionPostgreSQL
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