Most important SQL commands:
1. SELECT → retrieves data from a table or view
2. INSERT → adds new rows to a table
3. UPDATE → modifies existing rows in a table.
4. DELETE → removes rows from a table.
5. CREATE → creates a new database object such as a table, view, or index.

6. ALTER → modifies the structure of an existing database object
7. DROP → deletes a database object, such as a table or view
8. TRUNCATE → removes all rows from a table
9. JOIN → combines data from two or more tables

10. GROUP BY → groups of rows based on the values in one or more columns
11. ORDER BY → sorts the result set by one or more columns
12. HAVING → filters the result set based on aggregate values
13. DISTINCT → eliminates duplicate rows from the result set

14. LIKE → filters the result set based on a pattern match
15. UNION → combines the result sets of two or more SELECT statements