What is a database?
According to the video series, “SQL Server 2005 Express Edition for Beginners,” a database is defined as a computer file that is optimized to store up data in a structured manner. The way in which data is stored in a database is well organized and ensures that data is accurate and precise. Some databases are simply files while others require server software that manages the connection between these database files. This software majorly allows the accessibility to applications and their users. It also handles and retains the data in the databases. The creation and management of databases for applications is allowed by the SQL server 2005 edition which is a free application. The management of data is made easy by Relational Database Management System (RDBMS), which handles most intricate tasks that are related to incorporating data into one’s application. This enhances a high security of the data and hence prevents it from being corrupted (Microsoft ASP.net(a), 2005).
Data integrity is the correctness and accuracy of data and it is important in a database thus it needs to be maintained. Data integrity is an essential role of an RDBMS. A relational database does this by making sure that the data type is correct and it eradicates superfluous data that may result to incorrect versions of a single data unit. Furthermore, relation database ensures that the retrieval and manipulation of data is done efficiently and it eliminates the likelihood of accidental deletion of related data. RDBMS is most popular type of database and has several functions which include; offering security to the stored data, offering administration services which back up data and replicate of information, making the data available when required and lastly the capability to write and receive data using ad hoc reporting.
SQL server database is a complete toolset where the management tools and server tools administer the system and are used in data storage in the database. In a situation where there is a single server, a network web page is requested and this command goes to the web server and the internet information services retrieves the request and if it has a file extension the ASP.NET runtime engine interprets and retrieves the request. ASP.NET executes the command stored in the assembly which is generated when the web page is run for the first time which relies on a framework class library and ADO.NET communicates with the database whether to save or retrieve the information. ADO-NET is the bridge between a code and the database. The multiple servers are also known as N-Tier. In a tools viewpoint, the SQL server 2005 express edition gives an allowance for the opportune establishment and management capacity directly from visual studio IDE. It has visual drag and drop features that allow the functionality of integration of data, its recovery and operation. The SQL server has more functions in correspondence to maintenance and ad hoc reporting.
Understanding database tables and records
Data is maintained in a database by the use of tables, which are the building blocks of a database. A table is made up of columns and rows. A column on the other hand has three distinct pieces of information, which are; the name of the column, the type of data defined and stored in the column for instance numbers, dates and currency. The function of this is enabling data integrity, data usability and allocation of the right space in the file in which the data is stored. Each column can store one specific type of data and this enables data reliability. The third piece of information that defines columns is special properties for example the automatic numbering sequence and also it defines whether the column can empty. Each new instance of columns that joint structure a table is referred to as a row. A row is commonly termed as a” tuple” or as a” record”. A row of data is a unified set of single fields of information that work hand in hand to embody a complete unit. In a record, a field of data is usually a single value. When working with tables where its columns are defined and input can be added, data retrieved, updated and deleted in the database in a couple of ways which are by the use of table data view, using an ad hoc SQL statement and finally by use of an application such as ADO.NET (Microsoft ASP.net(c), 2005).
More about column data types and other properties
Data integrity is enforced by introducing special constraints in columns hence allowing performance of more complex operations such as looking up to see whether other values are present before it allows the insertion of data and factor is allowed in Structured Query Language (SQL).this constraints occur in several forms where they are data type constraints, referential integrity constraints and special rules. These constraints eliminate the more prone dangers that may occur when a person tries to put hazardous data in your database. In column data types it is advisable to use ‘int’ for big numbers while ‘smallint’ is for small numbers. In the case of using characters such as that of Chinese the ‘nvarchar’ is used. In order for the database to function appropriately, one should select the correct data type since too large of a data type ends up wasting space while too small of a data type causes artificial ceiling. An identity column is used in numbering a field automatically with regards to the previous field values for the existing records (Microsoft ASP.net(b), 2005).
Designing relational database tables
In designing relational databases, small related tables should be created to break the data up and link the tables using keys. There are two keys known as primary and foreign key. Primary keys specially classify a single row of a table. The identity column is used to guarantee that each row has a distinctive and unique feature. However foreign keys are used to link a record of data from the second table to the primary key of the first table. In the case where the primary key in one table and the foreign key of another table both having corresponding fields with slightly different names yet they hold the same data. Relational tables can be designed through a process known as normalization where non-relational tables are split into relational tables. There are a series of rules in the normalization process called forms and the more rules taken the more normalized the tables become. This tutorial has done a tremendous job since it teaches exclusively what a database is and it brings into light the database tables and records. It provides sufficient information about column data type and it finally teaches on how to design relational database tables.
References
Microsoft ASP.net(a), (2005). Designing Relational Database Tables. Microsoft ASP.net.
Microsoft ASP.net(b), (2005). More about Column Data Types and Other Properties. Microsoft ASP.net.
Microsoft ASP.net(c), (2005). Understanding Database Tables and Records. Microsoft ASP.net.