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This is quite an elemental question. Think about it- what would be termed atomic? One that cannot be divided, as from its Greek definition. Atomic values in a relational database mean that they cannot be further divided, according to domain rules defining that attribute. An attribute is a column in the table that people normally think of as a relational database, and the notion is pretty correct. Domain rules define what data and its type can go into a column, and others are inadmissible. For instance, let's say that the database of a particular bank is organized as a set of tables, that is it is relational in nature, and one particular table lists the details of all account holders with the bank. All these details can reasonably form the attributes of the bank's customers, and can therefore be allowed to represent columns in this table. Suppose we have a column that holds the account numbers of the customers, and the domain rule defines that an entry in this column must necessarily be a non-negative, non-zero, integer. By this rule, 2453536 is an atomic value, whereas No. 10, Bowers Avenue is not, since the latter can be split further, and it also does not satisfy the domain rules.
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What is atomicity property of a database?
A transaction must be an atomic unit of work; either all of its data modifications are performed or none of them is performed.
What is the difference between a key and a superkey?
In database a key is a field that we use to sort a data.whereas superkey is a subset of attribute so that no tuple have the same combination of values.
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.
Is it possible to perform a calculation within a database?
Yes you can. You can create queries that do calculations. You can write code for programs to do calculations in a database. Doing calculations is a significant element of what you do with a database, so yes you can do them within a database.
What is the atomic no and atomic mass of graphite?
Atomic number 6, atomic mass 12.
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 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.
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
What is schema instance?
In DBMS,Schema is the overall Design of the Database.Instance is the information stored in the Database at a particular moment.In programming,you declare a variable which corresponds to "Schema".But its values changes as and when required which corresponds to "Instance". Google about levels of Database Abstraction. Physical Schema describes database design at physical level while a logical schema describes the database design at the logical level.A database may also have several schemas at the view level, sometimes called subschemas, that describe different views of the database.
What is Schema and instances?
In DBMS,Schema is the overall Design of the Database.Instance is the information stored in the Database at a particular moment.In programming,you declare a variable which corresponds to "Schema".But its values changes as and when required which corresponds to "Instance". Google about levels of Database Abstraction. Physical Schema describes database design at physical level while a logical schema describes the database design at the logical level.A database may also have several schemas at the view level, sometimes called subschemas, that describe different views of the database.
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?=_
How is database structured?
That depends on the type of database it is and the design of the Database Annalist.
What is a logical database designer?
* Logical database design: * ensuring, via normalisation procedures and the definition of integrity rules, that the stored database will be non-redundant and properly connected; * Physical database design: * specifying how database records are stored, accessed and related to ensure adequate performance. What is logical database designerThe major role of logical database design is to transform the combined, reconciled data specifications into basic or atomic elements following the well established rules for well structures data specifications. With a complete logical database design in place an analyst begins to specify the logic of the particular computer programs and queries needed to maintain and report the database content. The person who maintain or responsible to perform the above task is known as Logical Database designer.
Custom Database Design?
form_title=Custom Database Design form_header=Design, develop and manage the database that fits your business needs. What do you need the database to offer?=_ Who will have access to the database?=_ Is this database for the internal or external public?= {(),Internal,External} Do you need the new database to integrate with a current system?= () Yes () No () Not Sure
Database Design Tools?
form_title=Database Design Tools form_header=Build a complicated database with ease by getting help from the experts! What tools do you want included on the database?=_ What is your budget for the database?=_ When does the database need to be completed by?=_
Could you explain the purpose of logical database design?
Logical database design is the process of designing the database at a conceptual level as opposed to a physical level. There are many advantages of conceptual database design, such as the ability to design the database without having to commit to a particular database management system, to produce a document that is readable and understandable to everyone in the company (not just the database person) and to produce an overall design document that can be saved as a part of the documentation of the database for future enhancement, maintenance and support work. Logical database design produces documents for use in the same way that architects produce blueprints for building purposes.
Overall design of a database software is known as?
Database architecture
