Are you a Business Analyst looking to use SQL queries to extract and analyze data from relational databases? Look no further! In this article, I’ll be sharing the most essential SQL queries that I, as a Business Analyst, use in my day-to-day work.
Not only that, but I’ll also provide you with easy-to-follow syntax examples, so that you can get started even if you’re a beginner. Get ready to take your data analysis skills to the next level!
Why SQL is important for business analyst
In case you missed the previous article, let me quickly summarize in this chapter why SQL is such an essential tool for business analysts. However, I highly recommend that you read the full article to get a complete understanding. So, let’s dive in and discover the key reasons why mastering SQL is crucial for every business analyst:
- SQL can provide valuable insights by extracting and analyzing data, which can aid in decision-making.
- Additionally, when troubleshooting application issues, analyzing the database can help identify the root cause.
- SQL is also useful for setting up test data sets.
- Exploring data, can sometimes help you analyze a bug and identify the root cause of the problem. You will be fixed if it is related to incorrect data or a problem with the application interface.
- Moreover, it can facilitate data migration from one application to another while ensuring data integrity.
- Finally, setting up reference data for a new application can be a snap with SQL. By writing scripts to automate this process, you can save valuable time for yourself and your team.
Main SQL Queries Used by Business Analyst
Here is a list of the main SQL queries that I commonly use as a Business Analyst:
The SQL Select statement
This is the query I use the most to retrieve data from one or more tables in a database. You can use it to retrieve specific columns or all columns from a table:
Example1: Here, we display the fields column1, column2, … of the table named ‘table1’:
SELECT column1, column2, ... FROM table1;
Example2: Here, instead, we’re displaying all the fields from the table named ‘table2’:
SELECT * FROM table2;
The SQL Join statement
You should use the join statement whenever you need to combine data from two or more tables based on a common column. It allows you to create a single result set that includes data from multiple tables.
Example: In this query, we combine the data from the Account and Opportunity tables based on a common column which is “Account ID” to create a single set which includes “Account Name”, “Opportunity Name” and the “Amount opportunity”:
SELECT account.name, opportunity.name, opportunity.amount FROM account INNER JOIN opportunity ON oppotunity.parent =account.id;
The SQL Aggregate functions
I often use the aggregate functions such as COUNT, SUM, AVG, MIN, and MAX to summarize data and provide insights into business trends.
Example: This query returns the number of rows in the table account. The term “AS NumberOfAccounts” define an alias name for the column to display. Otherwise, the column name will be “count(*)”.
SELECT COUNT(*) AS NumberOfAccounts FROM account ;
The SQL Group by statement
You should use the group by statement to group data by one or more columns. It allows you to aggregate data and perform calculations on groups of data. It’s often used with aggregate functions (
SUM(), …) to group the result by one or more columns.
Example : Here we count the number of opportunities per account (which corresponds to the parent column in the opportunity table)
SELECT COUNT(*), parent FROM opportunity GROUP BY parent;
The SQL Where statement
You shoud use the where statement to filter data based on specific conditions. It allows you to narrow down your results to only the data that meets your criteria.
Example : Here, we want to display the opportunities linked to the parent account whose id is ‘145577’:
SELECT * FROM opportunity where parent ='145577';
The SQL Order by statement
I use the order by statement to sort data in ascending or descending order based on one or more columns.
Example : The same last example, but here we sort the results by creation date in descending order:
SELECT * FROM opportunity where parent ='145577' Order by creation_date Desc;
By using the SQL queries above, you can quickly and easily analyze data, uncover trends, and provide valuable insights to your organizations.
How many sql languages are there?
SQL, or Structured Query Language, is a standard language used for managing and manipulating relational databases. While there is a standard SQL syntax, each database management system (DBMS) may have its own specific implementation of SQL with additional features or variations.
For example, MySQL uses a slightly different syntax than Microsoft SQL Server, and both of these differ from Oracle’s implementation of SQL. Some of the differences between SQL syntax in different DBMSs include small syntax variations for creating tables and indexes, defining data types, and using aggregate functions.
But in general, if you’re new to SQL, it’s a good idea to focus on learning the standard SQL syntax first, and then adapt to the specific syntax of the DBMS you’re using.