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SQL · skill quizzes

SQL quizzes

Test your knowledge with skill-focused quizzes. Each quiz targets one specific skill — answer first, score at the end, then review every miss with worked solutions.
61
Quizzes
617
Questions
01
Aggregates with WHEREIntermediate
10 questions · 15 min ·
02
Avoiding Non-Aggregated ColumnsIntermediate
10 questions · 15 min ·
03
Basic Aggregate FunctionsIntermediate
10 questions · 15 min ·
04
Computing Derived AggregatesIntermediate
10 questions · 15 min ·
05
Grouping SetsIntermediate
10 questions · 15 min ·
01
ALTER TABLEIntermediate
10 questions · 15 min ·
02
CREATE TABLEIntermediate
10 questions · 15 min ·
03
DELETE with WHEREIntermediate
10 questions · 15 min ·
04
Table ConstraintsIntermediate
10 questions · 15 min ·
05
TransactionsIntermediate
10 questions · 15 min ·
06
UPDATE with WHEREIntermediate
10 questions · 15 min ·
01
Checking NULL RatesBeginner
9 questions · 14 min ·
02
Identifying DuplicatesIntermediate
10 questions · 15 min ·
03
Integer Division in MetricsIntermediate
10 questions · 15 min ·
04
Join Duplication IssuesIntermediate
10 questions · 15 min ·
05
Reconciling AggregatesIntermediate
10 questions · 15 min ·
06
Three-Valued Logic & NULLIntermediate
15 questions · 23 min ·
07
Validating Row CountsIntermediate
10 questions · 15 min ·
01
CASE WHEN for CategoriesBeginner
9 questions · 14 min ·
02
COALESCE & IFNULLIntermediate
10 questions · 15 min ·
03
Creating Flags & BucketsIntermediate
10 questions · 15 min ·
04
Date Range FilteringIntermediate
10 questions · 15 min ·
05
Date/Timestamp ParsingIntermediate
10 questions · 15 min ·
06
String FunctionsIntermediate
10 questions · 15 min ·
01
Many-to-Many ModelingIntermediate
10 questions · 15 min ·
02
NormalizationIntermediate
10 questions · 15 min ·
03
Primary & Foreign KeysIntermediate
10 questions · 15 min ·
01
Avoiding Join MistakesIntermediate
10 questions · 15 min ·
02
Bridge TablesIntermediate
10 questions · 15 min ·
03
LEFT JOINIntermediate
10 questions · 15 min ·
04
Multi-Key JoinsIntermediate
10 questions · 15 min ·
05
Multi-Table JoinsIntermediate
10 questions · 15 min ·
06
RIGHT JOIN & FULL OUTER JOINIntermediate
10 questions · 15 min ·
07
Self-JoinsIntermediate
10 questions · 15 min ·
01
EXPLAIN/QUERY PLANIntermediate
10 questions · 15 min ·
02
Index BasicsIntermediate
10 questions · 15 min ·
03
Indexes for PerformanceIntermediate
10 questions · 15 min ·
01
DISTINCTIntermediate
15 questions · 23 min ·
02
IN, BETWEEN & LIKEIntermediate
10 questions · 15 min ·
03
IS NULL / IS NOT NULLIntermediate
10 questions · 15 min ·
04
LIMIT/TOPIntermediate
10 questions · 15 min ·
05
Multi-Column OrderingIntermediate
10 questions · 15 min ·
06
ORDER BYIntermediate
10 questions · 15 min ·
07
SELECT QueriesIntermediate
10 questions · 15 min ·
08
WHERE FilteringIntermediate
10 questions · 15 min ·
01
Communicating Query AssumptionsIntermediate
10 questions · 15 min ·
02
Defining & Implementing MetricsIntermediate
10 questions · 15 min ·
03
Parameterized Reporting QueriesIntermediate
10 questions · 15 min ·
01
Identifying KeysIntermediate
10 questions · 15 min ·
02
NULL & MissingnessIntermediate
10 questions · 15 min ·
03
Set-Based ThinkingIntermediate
10 questions · 15 min ·
04
SQL Dialect DifferencesBeginner
9 questions · 14 min ·
05
Table AliasesIntermediate
10 questions · 15 min ·
06
Table RelationshipsIntermediate
10 questions · 15 min ·
07
Tables, Rows & SchemasIntermediate
10 questions · 15 min ·
01
Common Table Expressions (CTEs)Intermediate
10 questions · 15 min ·
02
EXISTS vs. INIntermediate
10 questions · 15 min ·
03
Recursive CTEsIntermediate
10 questions · 15 min ·
01
Ranking FunctionsIntermediate
10 questions · 15 min ·
02
Running Totals & Moving AveragesIntermediate
10 questions · 15 min ·
03
Windowed AggregatesIntermediate
10 questions · 15 min ·