Data integrity, Database Management System

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You are required to implement integrity constraints within the database to enforce the following requirements: 
For Projects:

Start date must be supplied.
Start date cannot be in the past.
Finish date must be on or later than the start date.
Must have a supervisor value (supervised by cannot be null).
For Activities
Location must be supplied.
Finish time can be no later than 11.00pm.
Number of volunteers required must be greater than zero.
Date cannot be in the past.
Information requests

Create queries to answer the following information requests. Note: Do not use the Access query builder (QBE) to create your queries - you should type the queries in manually using SQL view.

1. List details (type, name) of all assets with a type of "Skill". Sort the list in alphabetical order of asset name.
2. List all details of projects that have been finished in the last ten days.
Hint: Use DateDiff function.
3. List the name and contact details of any members who have not yet volunteered for an activity. Note: It is not possible to answer this query with an inner join.
4. List the name of each member who may be able to contribute a trailer to a project.
5. How many members are able to provide cooking skills? Your result should be a single column with the heading ‘Number of Cooks'.
6. For each project, show the project name and the total number of volunteers required for all activities associated with that project.


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