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* As explained throughout this course, entity relationship modeling is a critical element of database design. If the database is not properly modeled, it is unlikely that the database will be properly developed. Using this knowledge, explain the key reasons why entity relationship modeling is important, and determine at least (1) way in which it impacts the overall development of the database.

Unique Column and Table Names: A column name within the table is unique because it is referenced by its table name. RDBMS does not restrict other tables to use same column names because they are identified by their table. Similarly table names within a database needs to be

If we consider an example of a database for billing the claims to the provider, we have two tables in the database as ‘Claims’ and ‘Provider’. ‘Claims’ have the claim information such as (ClaimNumber, ClaimType, Type of service, Admission details) and ‘Provider’ have the provider information such as (ProviderID, FederalTaxID, NPI, PointOfService). The primary keys for ‘Claims’ is “ClaimNumber” and for ‘Provider’ is “ProviderID”.

There will be many different constraints in the database. An example of a constraint is one if the students' GPA will have to be between 0.00 and 4.00. Another example would be that each class can only have one instructor. There would be a constraint on the social security number ensuring that there are only nine numbers and in the format is xxx-xx-xxxx, and each individual number would be between 0 and 9. There would be a constraint for the telephone numbers as well. Each individual number would be between 0 and 9 in the format of (xxx)-xxx-xxxx.

3) The SQL keyword PRIMARY KEY is used to designate the column(s) that are the primary key for the table.

b) You are to clearly mark Primary and Foreign Keys as shown in the sample below:

Task 4 - P4 Create features in data entry forms to ensure validity and integrity of data:

In most cases there is no need for a one-to-one relationship as the contents of the two tables can be combined into one

The entity integrity constraint says that if a relation R2 includes a foreign key FK matching the primary key PK of other relation R1, then every value of FK in R2 must either be equal to the value of PK in some tuple of R1 or be wholly null.

You are going to follow the procedure described in class to relate the Vendor table to the Item table. They will be related via the Vendor Table’s VENDOR ID to the Item Table’s VENDOR ID. Before you create your relationship, you must be sure that at least one record match exists between the two tables. When you create your relationship, you must be sure to specify that you will be enforcing referential integrity.

3. Evaluate all relationships of each entity within your database solution using the Crow’s Foot notation. Include all data elements, entities, relationships (such as 1: M, 1:1, M: N), and cardinalities for the department store database in your diagram. Note: The graphically depicted solution is not included in the required page length.

The primary keys serve a purpose of distinguishing one of the fields as important. These are related to the entities because it allows them to have a key makes each candidate, object or customer specific in a

Relational Database Management System is a database where data is represented as a set of relations in which data is stored. RDBSM is the basic for SQL. RDBSM contains a table (Is where the data of RDBMS is stored in) and the table contains a field (It is the smaller pieces of the table/ attributes of the table.), records (Also known as a row. It is a single entry in the table. It lies horizontally on the table) and columns (Columns lie vertical on the table. It contains all of the information related to a single field/ attribute). Constraints (Rules) can be enforced on a RDBSM. Example: Unique constraint (To ensure that all the data in a column is of different values), Not Null constraints (Set in place to ensure that a columns cannot have a null value), Primary key (Ensures uniquely identified records in a table), Foreign key (Ensures that

In a RDBMS, the tables will have an identifier called primary key. Data values will be stored in the form of tables. The relationships between these data values will be stored in the form of a table as well. Every value stored in the relational database is accessible. This value can be updated by the system. The data in this system is also physically and logically

Drag a field (typically the primary key) from one table to the common field (the foreign key) in the other table. To drag multiple fields, press the CTRL key, click each field, and then drag them.