Data Analyst Interview Questions: SQL Series
Hey there everyone. Of course, it’s Maria, your favourite Data Explorer, here 😁. Today, we’ll be starting our 4-week long Data Analyst Interview Questions series, beginning with the SQL (Server) series. For those who read my SQL for Healthcare, you’ll see that this streak was originally achieved on LinkedIn and Twitter. After some reflection, I’ve decided to bring these posts over to this platform. You all are welcome. 😌
The aim of this exercise is to answer and explain some of the frequently asked data terminologies and interview questions I’ve come across. Also, later on in the series, we’ll be answering some of the data analyst interview questions shared by Jessica Ayodele, a well-known and reputable senior data analyst and founder of DataTech Space. To gain a headstart, you could go through some of these questions on her LinkedIn page here.
As I stated earlier, this series spans for 4 weeks, where we’ll discuss SQL, Excel, Power BI, and finally, Python topics. For the SQL series, we’ll be talking about views, some window functions, subqueries, and so on. Today, though, I’ll be dropping the link to a SQL Server tutorial playlist by Kudvenkat. This playlist is so well-detailed and informative, perfect for SQL learners, intermediate users, and even advanced programmers. In this playlist, you’ll learn all about:
▪ Basic and Advanced/Intelligent joins in SQL Server
▪ Different ways to replace NULL in SQL Server
▪ Difference between Union, Union All and Joins
▪ Stored Procedures (Advantages of stored procedures, output parameters, return values and the difference between them)
▪ Built-in string functions (ASCII, CHAR, CHARINDEX, LTRIM, RTRIM, LOWER, UPPER, LEFT, RIGHT, PATINDEX, REPLACE, SPACE, SUBSTRING)
▪ DateTime data types (time, date, smalldatetime, datetime, datetime2, datetimeoffset)
▪ DateTime functions (GETDATE, ISDATE, DAY, MONTH, YEAR, DATENAME, DATEPART, DATEADD, DATEDIFF)
▪ Cast and Convert functions
▪ Mathematical functions in SQL Server (ABS, CEILING, FLOOR, POWER, SQUARE)
▪ User-defined functions (Scalar functions, Inline table-valued functions, multi-statement table-valued functions)
▪ Temporary tables (Local and Global)
▪ Indexes (Clustered/Nonclustered, Unique/Nonunique, Uses of Indexes)
▪ Views (Advantages, Updatable views)
You can access this playlist here. Tomorrow, we’ll be discussing views in SQL, and differences between views and stored procedures. If you haven’t read up my previous articles, now’s the perfect time to do so. They are quite informative and super fun to read. Go read them up now!
If you have any topic in particular you’d like to be discussed, whether one that’s been bugging you with its complexity, or one you just need more light to be shed on, do leave a comment in the comments section; I’ll try my best to answer these carefully and in full detail, and if it proves to be too arduous for me (dear God I hope it doesn’t), I’ll do well to leave other resources for you to go through. And of course, if you find these posts satisfyingly educative, or just eye-opening, give them lots of claps and leave me encouraging comments. So excited to go on this 4-week long journey with you all. Hope to see you here for tomorrow’s discussion. 🤗🤗
