Intermediate SQL
Intermediate SQL Lessons
Browse every intermediate SQL topic, organized into 8 practical learning paths.
Grouping & Aggregation
GROUP BY, HAVING, conditional aggregation
- SQL GROUP BY
- SQL GROUP BY One Column
- SQL GROUP BY Multiple Columns
- SQL GROUP BY with Aggregate Functions
- SQL HAVING
Conditional Logic
CASE WHEN, COALESCE, NULLIF
Joins
INNER, LEFT, RIGHT, FULL OUTER, SELF
Set Operations
UNION, INTERSECT, EXCEPT
Date & Time
EXTRACT, DATE_TRUNC, INTERVAL, YTD/MTD
String Functions
CONCAT, TRIM, SUBSTRING, SPLIT_PART
NULL Handling
three-valued logic, NULL in joins/aggregates
- Understanding SQL NULL
- SQL NULL vs Zero
- SQL NULL vs Empty String
- SQL Three-Valued Logic
- SQL NULL in Comparisons
Numeric Functions
ROUND, percentages, division by zero