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* Alternate key - An alternate key is any candidate key which is not selected to be the primary key
* Candidate key - A candidate key is a field or combination of fields that can act as a primary key field for that table to uniquely identify each record in that table.
* Compound key - compound key (also called a composite key or concatenated key) is a key that consists of 2 or more attributes.
* Primary key - a primary key is a value that can be used to identify a unique row in a table. Attributes are associated with it. Examples of primary keys are Social Security numbers (associated to a specific person) or ISBNs (associated to a specific book).
In the relational model of data, a primary key is a candidate key chosen as the main method of uniquely identifying a tuple in a relation.
* Superkey - A superkey is defined in the relational model as a set of attributes of a relation variable (relvar) for which it holds that in all relations assigned to that variable there are no two distinct tuples (rows) that have the same values for the attributes in this set. Equivalently a superkey can also be defined as a set of attributes of a relvar upon which all attributes of the relvar are functionally dependent.
* Foreign key - a foreign key (FK) is a field or group of fields in a database record that points to a key field or group of fields forming a key of another database record in some (usually different) table. Usually a foreign key in one table refers to the primary key (PK) of another table. This way references can be made to link information together and it is an essential part of database normalization
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What database types is useful for storing java applets as well as processing large numbers of transactions?
OODBMS, object oriented database management systems
What is the net driver to access the database?
Question doesnt make sense. There are tens of database types availible. Each using one or two drivers.
What is the data schema in a database?
Logical Structure of database is know as database schema. All database entities are defined and relation between then is represented in structured way. It includes all constraints to be apply on each identity.
Is 'A database uses characteristics such as field size and data type to define each field' false?
No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.No it is not false. Database fields do have field sizes and data types.
What are Field Types in Access?
Data types. Field types in Access (The absolute lowlevel Database engine, just above text files) include: Text Number Yes / No These fields all have charistica that decide length, decimal spaces, default values and such. Using the correct field types for data, and not just text for it all, will result in faster computing and easier coding.
Types of keys?
There are many keys in database each having particular use. Types of keys in database are : Primary key, candidate key, alternate key, foreign key, surrogate key.
How much types of keys are available in dbms?
There are five types of keys in database management system . The name of the five keys are as follows .:1) surrogate key -which is the system generated primary key .2) Primary key - same function as surrogate key but user defined.3) candidate key -combination of two more keys.4) alternate keys - alternative for candidate keys.5) foreign key - primary key of another table.There are five types of keys in database management system.These five keys are surrogate, primary, candidate, alternate, foreign keys .
What are secondary keys?
Secondary keys are the database keys that hold the physical location of a portion of a record in a database or file. They provide a secondary way of accessing the information.
What type of information is kept on a database?
All types of information may be kept in a database.
What are the basic components of a database?
Tables, Entities, Attributes, Primary Keys, and Foreign Keys
How does a database store data about its tables?
A database is used to store data in its tables by a specified number of rows and columns. Each database also uses specific cells, foreign keys, and unique keys.
What is data set in c sharp?
An in-memory database. The database contains tables and constraints, and data.
How many Auto Keys macros can be created in a database?
4
Types of databases in sql server 2005?
Types of Database in sql server 2005:- 1.Master Database 2.Tempdb Database 3.Model Database 4.MSDB Database 5.Resource Database
3 types of database in a typical organization?
network database tree database rdbms
What is the meaning for primary key in database?
With reference to Databases, what are Primary keys?
When you initially create a database you define its that is you assign names and types to all the fields?
Structure
