From the course: Introduction to Career Skills in Data Analytics

Relational databases

From the course: Introduction to Career Skills in Data Analytics

Relational databases

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- Have you ever really thought about how systems store data? I bet if you're a new analyst, you have not gotten that deep into the idea of how data is stored, but you just know that it is stored. Relational databases have been around for a while and you will hear people talk about SQL databases or SQL scripts or statements. A data analyst doesn't have to be fluent to be effective. You can do a lot with just being somewhat literate with SQL. This is a key area that you can further study if you're interested. RDBMS stands for Relational Database Management Systems and server technology, like Microsoft SQL Server, can store these databases. There are others. Even something as simple as an Access database has relationships and relational data. We need to go back one step and discuss structured data. When you work with a spreadsheet that has column headings and data values, then you're actually working with structured data. This data has a field name, we see it in the column headings, and then it has a data type and a value. When we build relational databases, we build structured data sets that are stored in the form of tables. These tables then become connected through a relationship between key fields. These key fields are unique identifiers that help control the data that can and cannot go into a table. When structured data is defined and then stored into tables and then the tables are related, this creates a relational database. These relational databases are used to hold information and we as data analysts use this structured and stored data to build reports, visuals, and analyze data. One thing that is important to note is that you as the data analyst must understand the structure that is used to store the data does not always make it easy for reporting. Why? The rules for effective storage are different from the rules used to combine data for reporting. They are two very distinct roles and functions, even if they work with the same data. As an analyst, you do not have to know how to design large-scale data systems, but you will want to understand some database design techniques so that it makes understanding someone else's design easier.

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