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Explain what cardinality constraints are and how they impact on database design?
Wiki User
∙ 14y ago
A Cardinality Constraint is when a certain relation can only have a certain number of instances for a relationship. For example, a Voter can only vote once in an election. Thus, there needs to be a cardinality constraint on the relationship VotedIn that relates a Voter to Election.
Wiki User
∙ 14y ago
Cardinality constraints are rules that define the relationships between tables in a database. They determine how many instances of one entity can be associated with another entity. For example, a cardinality constraint of "one-to-one" means that each instance of one entity can be associated with only one instance of another entity. Cardinality constraints impact database design by helping ensure data integrity and preventing inconsistencies or anomalies. They guide the creation of tables, their relationships, and the use of foreign keys for maintaining data relationships.
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Explain the steps in the design of an MIS?
1. Data collection through interview, source documents and personal observation. 2. Defining the problem in deatil. 3. Setting the system objective. 4. Establishing constraints. 5. Determining information needs and sources. 6. Develop alternative designs and select the best. 7. Documenting the conceptual design. 8. Detailed system analysis
What are some experimental design flaws that may explain why you don't get 100 percent yield?
What are some experimental design flaws that may explain why you don't get 100% yieldin the balloon lad
Two principal integrity rules for the relational model?
Integrity Rules Although integrity rules are not part of normal forms, they are definitely part of the database design process. Integrity rules are broken into two categories. They include overall integrity rules and database-specific integrity rules. == The two types of overall integrity rules are referential integrity rules and entity integrity rules. Referential integrity rules dictate that a database does not contain orphan foreign key values. This means thatEntity integrity dictates that the primary key value cannot be Null. This rule applies not only to single-column primary keys, but also to multi-column primary keys. In fact, in a multi-column primary key, no field in the primary key can be Null. This makes sense because, if any part of the primary key can be Null, the primary key can no longer act as a unique identifier for the row. Fortunately, the Access Database Engine (Access 2007's new version of the JET database engine, available with the new ACCDB file format) does not allow a field in a primary key to be Null.Database-Specific Rules The other set of rules applied to a database are not applicable to all databases but are, instead, dictated by business rules that apply to a specific application. Database-specific rules are as important as overall integrity rules. They ensure that only valid data is entered into a database. An example of a database-specific integrity rule is that the delivery date for an order must fall after the order date.
If a design has a total of 42 sides how many hexagons are in the design?
there is 7 hexagons in the design
How can you design a multiband filter?
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Database Design?
form_title=Database Design form_header=Transform your company by incorporating a new database design. What program will the database be used with?=_ Please explain what you will be using the database for?="" Do you have a database that you're already using?= () Yes () No
Could you explain the purpose of logical database design?
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Database?
form_title=Database Design form_header=Transform your company by incorporating a new database design. What program will the database be used with?=_ Please explain what you will be using the database for?="" Do you have a database that you're already using?= () Yes () No
Design a Web Database?
form_title=Design a Web Database form_header=Hire a developer to design a database to complement your business. What kind of business is the database design for?=_ What will you need the database design to offer?=_ Will you need ongoing support for the design?= () Yes () No () Not Sure
What are the responsibilities of the database designer?
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Is possible that during the physical database design and creation step of database development you might want to return to logical database design activity?
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Discuss various errors that occur during database design. explain various database integrity issues in detail.?
i am not aware about it.if u get to know then let me know
What is database design?
Design of the database (Database Design) refers to a given application environment, optimize the structure of the database, the database and applications, which can efficiently store data to meet the application needs of various user information needs and processing requirements). At www. myelibrary.net.In you can clearly understand what is the database design.
What are some common constraints in the field of engineer design?
The answer is engineer and design.
What is the purpose of design constraints?
The purpose of design constraints is to limit the cost and size of a project. Without them, designs would simply not be feasible in most instances.
What is design constraints?
Constraints are things that the design of the particular object MUST have and they must be included in the final design. Considerations are things that should be thought about in the design process and may or may not be included in the final design
Marketing Database Design?
form_title=Marketing Database Design form_header=Successful marketing comes from a well-designed database. Have one designed by a professional. What does your business do?=_ What is your budget for the database design?=_ Who is your target audience?=_ When does the database need to be completed?=_
