Role preparation

Database and SQL Developer interview questions and answers.

Query performance, indexes, and transaction safety.

Questions

Technical questions to practise out loud

  1. 01

    How do composite indexes work?

    Show practical understanding of column order, leftmost prefixes, and query access paths.

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  2. 02

    How do you read a query execution plan?

    Show practical understanding of scans, joins, cardinality estimates, and bottlenecks.

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  3. 03

    How do locks and transactions affect database concurrency?

    Show practical understanding of isolation, lock scope, deadlocks, and consistency.

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  4. 04

    When do you normalise or denormalise data?

    Show practical understanding of when do you normalise or denormalise data?.

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  5. 05

    How does database replication affect design?

    Show practical understanding of how does database replication affect design?.

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  6. 06

    How do you investigate a database deadlock?

    Show practical understanding of how do you investigate a database deadlock?.

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  7. 07

    How do you validate database backups?

    Show practical understanding of how do you validate database backups?.

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  8. 08

    When do you consider database sharding?

    Show practical understanding of when do you consider database sharding?.

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  9. 09

    How do you secure database access?

    Show practical understanding of how do you secure database access?.

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  10. 10

    How do you paginate large SQL result sets?

    Show practical understanding of how do you paginate large sql result sets?.

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