NULL, CASE, Sorting, and Dates
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Finishing Query Foundations
NULL, CASE, Sorting, and Dates
Now that we've covered basic retrieval in SQL: Select, Where, From, clean query structure in SQL Query Order and Aliases, and predicate logic in Filtering: LIKE, IN, BETWEEN, AND, OR, NOT, we're ready for the beginner mistakes that show up constantly in interviews.
This lesson focuses on four practical query skills:
- Handling NULL correctly
- Creating readable labels with CASE
- Sorting results with ORDER BY
- Filtering date and timestamp values safely
These are still querying fundamentals. We are not combining tables yet — that comes next in Joins in SQL.

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