Create a comprehensive SQL quiz for senior developers. ## Target Audience Senior developers who interact with relational databases. This tests universal SQL knowledge that applies across PostgreSQL,
SELECT basics, WHERE clause, comparison and logical operators, NULL handling, ORDER BY, LIMIT/OFFSET, DISTINCT, aliases, and CASE expressions
30 questionsINNER JOIN, LEFT JOIN, RIGHT JOIN, FULL OUTER JOIN, CROSS JOIN, self-joins, join conditions, and multi-table queries
35 questionsNormalization forms, denormalization, foreign keys, constraints, primary keys, surrogate keys, entity relationships
35 questionsROW_NUMBER, RANK, DENSE_RANK, PARTITION BY, LEAD, LAG, FIRST_VALUE, LAST_VALUE, window frames
35 questionsGROUP BY, COUNT, SUM, AVG, MIN, MAX, HAVING, and combining aggregation with filtering.
30 questionsCorrelated and non-correlated subqueries, CTEs (WITH clause), recursive CTEs, EXISTS/NOT EXISTS, and query readability.
30 questionsINSERT, UPDATE, DELETE, UPSERT (INSERT ... ON CONFLICT / MERGE), transactions, and bulk operations.
30 questionsB-tree and hash indexes, composite indexes, covering indexes, query plans (EXPLAIN), index selectivity, and when not to index.
30 questions