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Indexing and Query Performance

MediumSQL · PostgreSQL00:00
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Your question is Indexing and Query Performance. Start with the requirements and the one table on the right.

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Problem

Explain the importance of indexing in databases.

Use the provided PostgreSQL tickets table to demonstrate a selective lookup. Write a query that returns open tickets created on or after January 1, 2025, and briefly explain how an appropriate index could improve this query.

Output

  1. One row per matching ticket with columns ticket_id, status, priority, and created_at
  2. Exclude tickets that are not open or were created before the specified date
  3. Sort by newest created_at first, then ticket_id ascending

Schema

tickets
ColumnTypeDescription
ticket_idPKINTUnique ticket identifier
statusVARCHAR(20)Current ticket status
priorityVARCHAR(20)Ticket priority
created_atDATEDate the ticket was created
Tablestickets
Your solutionPostgreSQL
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