SQL Server FAQs - Understanding SELECT Statements and GROUP BY Clauses

SQL Server FAQs - Understanding SELECT Statements and GROUP BY Clauses

A collection of 20 FAQs on SQL SELECT query statements. Clear answers are provided with tutorial exercises on simple SELECT query to select specific rows and returning specific columns; applying group aggregation functions on selected rows; dividing selected rows into multiple groups using GROUP BY and HAVING conditions; sorting selected rows and groups.

1. What Is a SELECT Query Statement?


2. How To Create a Testing Table with Test Data?


3. How To Select All Columns of All Rows from a Table with a SELECT statement?


4. How To Select Some Specific Columns from a Table in a Query?


5. How To Select Some Specific Rows from a Table?


6. How To Add More Data to the Testing Table?


7. How To Sort the Query Output with ORDER BY Clauses?


8. Can the Query Output Be Sorted by Multiple Columns?


9. How To Sort Query Output in Descending Order?


10. How To Count Rows with the COUNT(*) Function?


11. Can SELECT Statements Be Used on Views?


12. How To Filter Out Duplications in the Returning Rows?


13. What Are Group Functions in Query Statements?


14. How To Use Group Functions in the SELECT Clause?


15. Can Group Functions Be Mixed with Non-group Selection Fields?


16. How To Divide Query Output into Multiple Groups with the GROUP BY Clause?


17. How To Apply Filtering Criteria at Group Level with The HAVING Clause?


18. How To Count Duplicated Values in a Column?


19. Can Multiple Columns Be Used in GROUP BY?


20. Can Group Functions Be Used in the ORDER BY Clause?

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