Can someone please help me with these questions from my CMIS 320 class?

1) Explain why it’s a good idea to have DROP TABLE statements at the beginning of your DDL SQL script files that are used to create one or more tables.

2) How can you drop a table from your database that has one or more other tables referencing it with foreign keys?

3) What is a HAVING clause used for and how does this differ from a WHERE clause?

4) Give an example of how a subquery can be used in the WHERE clause of a SELECT statement.

5) Give your own example od SQL containing one of the following commands: CREATE, DELETE, UPDATE, SELECT, INSERT