Table of Contents
Introduction
Transact-SQL is a programming extension to the Sequence Query Language (SQL.) It includes transaction control, declared variables, the row processing and error handling operations. Applications that run on Transact-SQL do so by communicating with the SQL server (Henderson, 2000 p. 6). SQL statements are sent to the server where they are interpreted and processed. The most common Transact-SQL queries include the SELECT statement, row restricting, modification of search conditions and selecting columns. According to Petkovic (2008 p. 15), identifiers also form an important part of the T-SQL language. They are mainly used in the servers and databases. Some of the common identifiers include tables, data types, stored procedures, views and columns. Each identifier has a unique name which is assigned when an abject has been created. Identifiers are mainly used to identify objects (Petkovic, 2008 p, 17). Transact-SQL was developed by Microsoft to operate exclusively on SQL servers. It is considered to be one of the most secure software in the management of enterprise databases. The essay looks at various aspects of Transact-SQL including its structure, vulnerabilities, and application.
Structure of Transact-SQL
Basically, Transact-SQL is the only language that has been designed to work with an SQL server. This means that all other applications that require to be used alongside the SQL server must send in their data in Transact-SQL. This makes it possible for the application to process the query in a format that it can understand. Transact-SQL is a multifunctional language (Shapiro, 2002 p. 54). Besides enabling users to understand the existing functionalities, it allows the application of multiple extensions. Developers are able to implement complicated logics in the server. Transact-SQL language also allows users to control data access. Any unauthorized person can blocked from accessing various pieces of information. Statements declaring relational integrity (DRI) are also generated showing the authenticity and integrity of the information (Petkovic, 2008 p. 19). Business roles that will be implemented at the server level are also defined by the language.
Transact-SQL language has an in-built hierarchyid data type which makes storage and query of data much easier. Hierarchical relationships are usually defined items of data related to each other through a parent, child format. Some of the common hierarchical data that is stored in the SQL databases include the organization structure, the organizational structure, language taxonomy, and project tasks (Anley, 2002 p. 65). Hierarchyid data types are used to create tables that have a hierarchical structure. They can also be used to describe data stored in a different location. Hierarchyid functions are used to query and manage data.
Data types in Transact-SQL are mainly hierarchyid. Some of the main properties of these data types include the fact that the data is extremely compact (Anley, 2002 p. 67). They also allow in depth first order comparisons. Arbitrary insertions and deletions are also supported. Therefore, data editing and retrieval is much easier. The parent-child relationship allows the development of multiple relationships (Otey, and Conte, 2000 p. 108). Using Transact-SQL, developers are able to encode and decipher complex logic.
Transact-SQL Statements
The stored procedure is the most common statement in T-SQL. It is usually compiled and stored as a T-SQL code. The existence of similar views on the code generates an execution plan commonly referred to as the first time (Arief, 2006 p. 12). The main advantage of stored procedures is that they can select the required data and have it executed using any parameters.
Another group of T-SQL statements are the user defined functions. They take in parameters, carry out the required actions and finally return the results. All these functions are carried out in a single call. User defined functions are available in different categories, each having their own unique functionality (Arief, 2006 p. 14). Trigger statements are stored as T-SQL scripts. The script runs any other statement besides the SELECT function is issued on a particular table or view. The most commonly used trigger commands include AFTER and INSTEAD OF.
Programming T-SQL statements are used by IT professionals to develop and build sophisticated applications which are contained in the SQL servers (Otey, and Conte, 2000 p. 102). These statements enable the built applications to update, insert, or delete various pieces of data contained in the database.
The Common Language Runtime (CLR) integration T-SQL statements are used by developers to integrate the .NET framework (Arief, 2006 p. 16). The integration makes it possible for .NET enabled programming languages to be used on the SQL server.
Transact-SQL Functions
Transact-SQL functions are available in two different forms: Server built in functions, aggregate functions, ranking functions, rowset functions, scalar functions, and user defined functions (Anley, 2002 p. 72). Aggregate functions operate on a group of values but they return a single value.
Ranking functions return and ranking value in each of the queried row within the partition. Rowset functions tend to return objects which can be used as table references within the SQL statements (Anley, 2002 p. 75). Scalar functions are used to operate single values and they also return single values.
One of the main strengths of Transact-SQL language is that it supports analytical functions. This makes it possible for it to depict and handle complex tasks. Analytical functions are used by IT professionals to carry out common analysis operations such as ranking, percentiles, cumulative sums, among others all in a single statement (Anley, 2002 p. 75).
We can do it today.
Uses and applications of Transact-SQL language
Transact-SQL is the primary language used by developers in communicating with relational databases. The language not only acts as a communication tool but also enables users to fully utilize all the available tools in various applications. According to Petkovic, (2008 p, 22) transact-SQL make it easier to use databases. However, this is only possible if one is fully versed with the language.
There are many applications that make use of Transact-SQL language within the SQL server. First, it can be used to increase productivity applications in office settings. Various applications that have graphical user interfaces and make use of tables and columns can find Transact-SQL language quite useful. Various business applications especially where data storage is important can also make use of Transact-SQL language (Shapiro, 2002 p. 63). The business applications can either be developed for the business in-house or even purchased from vendors.
Transact-SQL is also used in web pages that extract data from SQL databases. It is also used in distributed database systems in the replication of SQL data in other databases. Transact-SQL language also helps to detach corrupted files from the web (Arief, 2006 p. 25).
Vulnerabilities to Transact-SQL
Despite the fact that Transact-SQL is one of the most secure platforms for developing distributed databases, there are still a number of loopholes that can be exploited by hackers for malicious purposes. Every feature that exposes the system is viewed as a potential risk. Different features differ in terms of their level of vulnerability (Arief, 2006 p. 26). It is important for developers to ensure that those risks that can be fixed are rectified.
One of the most significant vulnerability of Transact-SQL language is the absence of proper security policies. There is need to ensure that the existing laws and policies on the guidelines that should be followed by organizations are updated. Issues such as access to firewalls, protection from viruses and patching should be fully addressed (Shapiro, 2002 p. 76). The security of the T-SQL servers should also be implemented in accordance with the principle of least privilege (Otey, and Conte, 2000 p. 115). According to the principle, access should only be granted to an object based on its minimum level of security that it can be accorded. Security bulletins should also be closely monitored so as to ensure that the system security features are fully updated. Organizations that fail to update their security systems expose themselves to a myriad of threats.
The use of SQL servers over the internet can leave some standard ports open therefore exposing the network to possible attacks. To prevent this vulnerability, secure firewalls should be installed and updated at all times. Poorly done encryption can also expose SQL servers to possible attacks (Otey, and Conte, 2000 p. 118). The required certificates should be properly applied to verify the authenticity of the information. Poor use of self-certifications and extended periods of validation exposes the system to possible exploitation.
Unsecured accounts are a major threat to security. Where accounts need to be set up, they must be fully secured with passwords, the accounts settings must be done in accordance with the set guidelines. The passwords should be strong enough to avoid brute force and dictionary attacks by hackers (Shapiro, 2002 p. 79). The SQL server keys should be fully backed up, they should also be regularly changed to ensure that the system remains fully secure.
Conclusion
The development of T-SQL from SQL formed a very strong and secure tool for database development. It is considered to be one of the most secure languages in regard to data security. Developers find the language quite important for the development of various applications. The strengths of T-SQL are its ability to handle multiple functions and its ability to integrate with other languages. It is however important for organizations to ensure that they constantly update their security policies to ensure that their SQL servers are fully secure.
- Anley, C., 2002. Advanced SQL injection in SQL server applications.
- Arief, M.R., 2006. Pemrograman Basis Data Menggunakan Transact-SQL dengan Microsoft SQL Server 2000. Penerbit Andi.
- Henderson, K., 2000. The guru’s guide to Transact-SQL. Addison-Wesley Longman Publishing Co., Inc.
- Otey, M. and Conte, P., 2000. SQL Server 2000 Developer’s Guide. McGraw-Hill Professional.
- Petkovic, D., 2008. Microsoft Sql Server 2008 A Beginner’S Guide. McGraw-Hill Osborne Media.
- Shapiro, J., 2002. SQL Server 2000: the complete reference. McGraw-Hill, Inc..