Write definitions using your own words for the first 20 Key Terms on page 173 (C

Question

Write definitions using your own words for the first 20 Key Terms on page 173 (Concepts of Database Management 8th Edition) at the end of Chapter 5. Don't just copy and paste the definition from the book! Please take your time and write it as you write your own assignment that you want 100 grades on it! The definition must be related to the same chapter in the book NOT GENERAL DEFINITION. Do it correctly or leave it to please! Hand writes/Picture is Not working, Please answer in a way that I can copy and paste it easily, and don't miss any key term. Thanks!

1. alternate key

2.     Boyce-Codd normal form (BCNF)

3.     candidate key

4.     concatenation

5.     dependency diagram

6.     determinant

7.     first normal form (1NF)

8.     fourth normal form (4NF)

9.     functional dependence

10. functionally dependent

11. functionally determines

12. interrelation constraint

13. multidependent

14. multidetermine

15. multivalued dependence

16. nonkey attribute

17. nonkey column

18. normal form

19. normalization process

20. partial dependency

Explanation / Answer

Although I tries to explain all the terms but some of them are confusing and not able to clearly determine what was the context of it so won't able to that.

Alternate key: Any candidate key that has not been selected as the primary key. ALthough it is capable of primary key, has all the capability of it i.e. unique not null etc.

BCNF: A relation schema R is in BCNF if whenever a non trival functional dependanct X --> A holds in R, then X is ia superkey of R.
where Non Trival: If there at least 1 element on RHS that is not exists in LHS it is non trival. Every relation in BCNF is also in Three NF, however a relation in three NF is not necessarily in BCNF.

Candidate Key: Candidate keys are those keys which is candidate for primary key of a table. In simple words we can understand that such type of keys which full fill all the requirements of primary key which is not null and have unique records is a candidate for primary key. So thus type of key is known as candidate key. Every table must have at least one candidate key but at the same time can have several.

Concatenation: in the context of databases, refers to the joining together two or more things into a large one. In database parlance, the things being joined are generally two table fields which may be from the same or different tables.
For an instance in case of sql The Concatenate function combines multiple character strings together. Each database provides its own way(s) to do this:   MySQL: CONCAT( )

Functional dependency diagram (FDD): functional dependency is represented by rectangles representing attributes and a heavy arrow showing dependency. Fig. shows A functional dependency diagram for the simplest functional dependency, that is, FD: Y -> X.
In functional dependency diagram, each FD is displayed as a horizontal line. The left-hand side attributes of the FD, i.e. determinants, are connected by Vertical lines to line representing the FD. The right-hand side attributes are connected by arrows pointing towards the attibute.

Determinant: In a database table is any attribute that you can use to determine the values assigned to other attribute(s) in the same row.
Consider a table with the attributes ssid, f_name, last_name and dob. In this case, the field ssid determines the remaining three fields. The name fields do not determine the ssid because the firm may have more than one employee with the same first and/or last name. Similarly, the DOB field does not determine the ssid or the name fields because more than one employee may share the same birthday.

1NF: A relational schema is said to be in 1Nf if the values in the domain of each attribute of relation are atomic.
In other words only one value is asscoiated with each attribute and values is not set of values or list of values.

Fourth normal form (4NF): is a level of database normalization where there are no non-trivial multivalued dependencies other than a candidate key.
It builds on the first three normal forms and the (BCNF). It states that, in addition to a database meeting the requirements of BCNF, it must not contain more than one multivalued dependency.
Multivalued dependency is best shown using an example. In a table containing a list of three things - school subjects, the teacher in charge of each subject and the recommended book for each subject - these three elements (subject, teacher and book) are independent of one another. Changing the subject’s recommended book, for instance, has no effect on the subject itself. This is an instance of multivalued dependency: An item depends on more than one value.
In this instance, the subject depends on both teacher and book.

Functional dependency: It is a relationship that exists when one attribute uniquely determines another attribute.
If Rs is a relation with attributes M and N, a functional dependency between the attributes is represented as M->N, which specifies N is functionally dependent on M. Here M is a determinant set and Y is a dependent attribute. Each value of M is associated precisely with one N value.

Functional dependency: It is a relationship that exists when one attribute uniquely determines another attribute.
If R is a relation with attributes M and N, a functional dependency between the attributes is represented as M->N, which specifies N is functionally dependent on M. Here M is a determinant set and N is a dependent attribute. Each value of M is associated precisely with one N value.

Functional dependent: The function that depends by above functional dependant criteria.

Functionally Determines: Determining a column by calculating from other data given by user.
For an instance if user inputs DOB, determine its age.

Interarelation Constraint: An intra relation constraint limits the values of a column by a comparison to the values of another column in the same table.For example, a column named ProjectEndDate could be limited to a date that is later than the value ofProjectStartDate in the same row.
2) An interrelation constraint extreme values of a column by a comparison to the values of another column in a another table.For instance, a column named Worker On Project Start Date in the Student-work table could be restrict to a date that is later than the value of ProjectStartDate in the PROJECT table for the corresponding project.

Multivalued dependency: occurs when the presence of 1 or more rows in a table shows the existence of one or more other rows in that same table. Put another way, two attributes (or columns) in a table are independent of one another, but both depend on a third attribute. A MVD prevents the normalization 4 NF.

Non Key Attributes: are the one which are not candidate keys, there values needs not to be unique. They can not become Pk.

Nonkey Column: They are not considered by the Database when calculating the number of index key columns or index key size. An index with non-key columns can improve query performance when all columns in the query are addded in the index either as key or nonkey columns.

Normal Form: It is set of various forms in normalization standards, which holds various properties for the table, if some table satisfy all the requirement in that particular level then it is called that particular level normal form.

Normalization: It is a technique that is used when designing and again designing DBMS. Normalization is a process or set of defined forms used to optimally design a database to reduce redundant data. The actual defined forms of normalization, called normal forms.

Partial dependency: A nonprime attribute is functionally dependent on part of a candidate key.A nonprime attribute is an attribute that's not part of any candidate key.
For instance, let's start with R{PQRS}, and the functional dependencies PQ->RS and P->R.
The only candidate key for R is PQ. R and S are a nonprime attributes. R is functionally dependent on P. P is part of a candidate key. That's a partial dependency.

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