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SQL for Business: Introduction to SQL

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Information is the new oil’ is a common phrase used in this era of technological advancements. This phrase is often used to show the value and importance of data and information.

For businesses, well-established or small, data is the basis of their functioning.

Enterprise computing forms the epitome of data-driven businesses. However, dealing with data can end up becoming an economic burden. This can happen if the business does not set up well-detailed data management structures.

Structured data storage comes in. It helps manage data and offers other features such as data relationships.

Structured Query Language (SQL) is a programming language created by IBM in 1974. The language was meant to be used to manage relational databases.

SQL has various functions such as:

  1. Data input;
  2. Database querying; and
  3. Retrieving and filtering data in a database.

All the SQL functions can be summarized as relational calculus.

In this article, we will have a look at the basics of SQL for business.

Benefits of Learning SQL for Business

The advantages of using relational databases for managing business data are many. SQL was specifically designed to be used for managing big data. This means that SQL can handle large data volumes and a high number of transactions in a day.

Hiring a database administrator to manage the data for your business may be costly. Learning basic introductory knowledge about SQL or hiring outside SQL consulting services can help save money for your business.

In this era, learning any technical skill is very easy. Acuity Training is one of the organizations that offer training in technical skills at their offices or your preferred location.

These kinds of institutions teach basic material that covers SQL introductory training. They also have courses with complex specialized SQL functions. These include the implementation of SSIS for ETL operations and data transfer.

Another benefit of managing your business database is that it offers improved confidentiality. This is because you do not have to expose your data to a third party for management purposes.

Introduction to SQL

Introductory courses to SQL will cover the basics of the programming language. These basics contain guides on how to design a database and perform basic functions. The basic functions include data input, report generation, etc.

a) Database Design Techniques

The trick to having a perfect database is always in the design process. More often than not, database designers start constructing the database without planning the design.

That said, there are a few integral points to observe to ensure that a database will be well-designed and functional.

The first factor to keep in mind is to always have a unique field in every table on the database. A unique field refers to a set of characters or figures that are unique to every record inserted into the database.

In a school system, a student’s registration number is a unique identifying field. Unique fields are often used as the primary key in relational databases.

The second factor to observe deals with the primary key. You should set a primary key in all your tables. This will ensure that different tables are well linked with enforced referential integrity. In case you are ever in doubt, the primary key is always derived from a uniquely identifying data field.

The next step in the process is to define secondary keys. A secondary key is a unique data field on a table that is a primary key in another table. The secondary key links two or more tables.

During the database design process, it is also important to identify the correct data types for all record database entries. Failing to define the accurate data types can cause errors during data entry and manipulation.

The final step in database designing is the design of the database model. A database model is a diagram that defines a database’s logical structure.

b) Basic SQL Functions

Once the database is fully designed on paper, the design is now implemented in a database management system. Several database management systems use the SQL language.

Examples of these database management systems are MySQL, PostgreSQL, Microsoft SQL Server, Oracle Database, etc.

In learning, the first function that you will get to use is the CREATE DATABASE function. This is the function that is used to create a designed database. The function has a specific structure that will ensure that it runs properly and performs the desired function correctly.

After creating the database, the next task to perform is to create the various tables in the database. Data types of records in the table are defined when implementing this function.

A common mistake made by most people managing their databases is keying in data immediately after creating the tables.

This is a rookie mistake. This often leads to referential integrity errors if there are any errors during the data entry process. After creating tables, the next step is to construct and define the relationships between these tables.

Defining relationships before putting in data ensures that all records being input meet the referential integrity rules.

Referential integrity refers to the logical dependency between primary keys and foreign keys in relational databases. This ensures that a data record is valid and correct according to all references linked to it.

During initial data input, use sample data that has its outputs predetermined. Using this type of data, it is easy to test the database. This will ensure it is functional so you can now install the database and use real data.

After the database has been created and all tables and relationships worked on, you should now start learning data manipulation using SQL.

Conclusion

Based on the level of independence you seek in your business, you may have to take more courses on SQL. As seen, the introductory SQL course offers the basic skills required to design and construct a database.

If you intend to perform more complex functions with your database, you will have to take up more advanced courses. The advanced courses offer an in-depth look at the facilities that SQL programming language has to offer.