3 levels of SQL expertise

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What is the extent of your knowledge of SQL? Basic, intermediate or advanced?

• Basic: simple select queries with filtering, inner and left joins, aggregation, confident use of date functions, CASE statement, UNIONs etc., then state that you can create SQL queries to a basic level.
• Intermediate: CTEs and temp tables, window functions, string handling functions (like REPLACE, SUBSTRING, LEFT…