SQL.

Relational query language, optimization, and schema management. Covers 13 sub-skills.

• SQL · 1 of 3

  SELECT, WHERE & ORDER BY

  Which SQL clause filters rows based on a condition?

  AHAVINGBFROMCWHEREDORDER BY

• SQL · 2 of 3

  Subqueries & CTEs

  Which keyword introduces a Common Table Expression (CTE)?

  ATEMPBALIASCBLOCKDWITH

• SQL · 3 of 3

  Transactions & Isolation Levels

  Which anomaly can still occur under snapshot isolation but is prevented by serializable isolation?

  APhantom rows appearing on a re-run range queryBNon-repeatable reads of a row updated by a committed peerCWrite skew across concurrent transactionsDDirty reads of another transaction's uncommitted writes