DEV Community: Mohammad Meezan

My first SQL interaction

Mohammad Meezan — Tue, 30 Jun 2026 19:37:49 +0000

Today was my first day of learning SQL and my interaction with it was very unique its not like excel its different.
First I learned that database is a collection of data.
Then I learned about two types of database.

Relational Database:Data is stored in the form of rows and columns in it.MySQL,PostgreSQL etc are some examples.

2.NoSQL Database:Data is stored in non tabular form such as json files,documents etc.

Then I studied about the CRUD operations in SQL using various SQL commands.

1.SHOW DATABASE:To show the databases lying in my sql application.
2.CREATE DATABASE:To create a new database in my sql application.
3.USE:After creating the database I used this command to use the database I created.
4.SELECT DATABASE():Then I used this command to know whether the database I created is selected or not for doing further operations.
5.CREATE TABLE:I used this command to create a table inside my database.And I also added which datatype will be added in given details.And I also added NOT NULL command,so that my entries would not get any null values.
6.DESC:This command I used to get the description of table.
7.INSERT INTO:Then I used this command to insert the specific details of each features in the column.
8.SELECT:This command is use to retreive rows of data from the table I created.
9.FROM:This command is use to specify the tables from which you want to retrieve or delete the data.
10.UPDATE:This command is use to update the details inside the table in MySQL.
11.DELETE:It is use to delete specific feature inside the table in MySQL.

The issues that I encountered and how I fixed it

1.While running the create table command it told my you have a syntax error then I saw that a comma(,) is missing after filling the datatype of EID then I put the comma and my command ran.

2.I was not able to implement the INSERT INTO command then I saw that in the varchar datatype inputs I forgot to put quotation marks then I put the quotation marks and my command ran properly.

And in this way I learned SQL and solved the issues I encountered today.

My 3rd excel project

Mohammad Meezan — Sun, 21 Jun 2026 20:52:59 +0000

I picked up a random dataset of amazon book sales of 10 years from kaggle and started exploring and analysing it.

1.Data Cleaning

At first I opened my dataset in power query and found there were many duplicate values in my book name section then I removed the duplicates.Then I found in the price section there was some 0 values so the price of book can't be zero so I took the mean of the price array and replaced all zeroes with mean to make my analysis better and then I loaded my data and started to analyse it.

2.Data Analysing

I did various analysis using pivot tables and some excel function.

1.Year wise sales analysis:In this analysis I found in which year the sales was high in the first few years then it started droping down and as the sales goes down also the moeny generation goes down.

2.Genre analysis:In this analysis I found highest no of boos that sold were non fiction over the last 10 years while the difference in the no of books between the fiction and non fiction books is of just 31.

3.User rating analysis:In this analysis I found the books below 4.3 rating are sold less as compared to books above 4.2 ratings.Books above 4.2 are sold in highest amount.Only 22 books were sold in past 10 years of below 4.3 rating while 329 books above 4.2 rating were sold in past 10 years.

4.Reviews analysis:In this analysis I learned two new functions and I found the insight that the book that got the highest number of reviews by people is Where the crawdads sing and the no of reviews it got is 87841.

The two new functions I learned was match and index.

At first I tried to implement the vlookup function but vlookup function can only look from right to left not from left to right and I had to look from right to left then I used the match function.At first I calculated the maximum value in reviews section using max function.Then I got 87841 as result then I implemented match function to know in which row 87841 lies then I found it lies in the 344 row and then I used index function to analyse in the 344 row which book is lying in the name of book section then I found it is the book Where the crawdads sing.

The important decisions the business owner should take is:

1.He should bring more stocks of books above the rating of 4.3 cause the books above these ratings are highly sold.

2.He should sell more non fiction books than fiction books but he should also keep fiction books in a good amount cause there is just a difference of 31 books.

3.He should also bring Where the crawdads sing in higher numbers cause its reviews are also high and its also rated 4.8.

And here my analysis got completed.

My first data analytics projects

Mohammad Meezan — Wed, 10 Jun 2026 19:44:44 +0000

Today I got hands on my first data analytics project which was a healthcare dataset.

First I got the dataset and then I did the following steps.

I understood the data first as It was a healthcare data there was given name of patients,number of patients,their disease,their medication,their blood groups etc.

2.Then I uploaded the data in the power query to clean the data in power query I found in the gender category there was 3 options given as male,female and m where I replaced value m as male.In the bloodtype feature I found very inconsistency where there was O- and O-ve both were present even every blood type was like that so I replaced the value O-ve to O- and I did the same process for all blood types.I also corrected the alphabetical writing of medical condition by transforming them to capitalize each word cause I found alphabetical inconsitency in them,then in billing amount I found an error in the data where I remember the number it was written as 6452O which I replaced it with 64520 cause O is an alphabet.Even in the admission type there was two same like options which was emergency and emer then I replaced the values emer with emergency.Even I added an conditional column which was an age bucket column where the condition was if the person is below 30 consider him/her as young and if below 60 consider as middle and if these two conditions are not fulfilling then consider as senior.And then my data got cleaned and prepared.

3.Then I did the analysis using pivot tables and here is the analysis:

1.Admission type analysis:In this analysis I analyse the no of patients admitted on the basis of elective,emergency and urgent.And I found highest no of patients were admitted in emergency in the hospital and even I analysed the average billing amount in the above 3 scenarios and found the patients in emergency had more average billing amount as compared to elective and urgent.

2.Age bucket anlysis:Here is analysed the no of patients based upon the age bucket factor and found middle aged people were the most who were admitted into the hospital but I also analysed the average billing amount among these age groups and found senior patients have highest average billing amount this means the cost of treating the seniors is bit high as compared to young and middle ages.Even I also used filter you can see in my excel sheet.

3.Insurance provider analysis:Here I analysed how many patients has took the medical insurance of the 5 companies Aetna,Blue cross,Cigna,Medicare and United healthcare and found most of the patients took the insurance medicare but the average billing amount of the patients of Cigna was highest.I also filtered the insurance patients on the basis of their medical condition and age bucket.

4.Medication analysis:Here I analysed the number of patients taking 5 different medications and found most patients were taking penicilin but found the average billing amount was higher for patient who was taking lipitor medication.I also used the filter on the basis of medical condition you can see it in my excel sheet.

5.Bloodtype analysis:Here I analysed the no of patients on the basis of bloodtype and found patients with AB- bloodtype were the highest.I also filtered the bloodtype count of patients on the basis of medical condition.

6.Gender analysis:Here I analysed the no of patients on the basis of male and female and found female were the most who were admitted into the hosiptal.I also used the filter of medical condition to find the number of males and females admitted with specific disease.Even I filtered it with age to determine no male and females in specific age groups.

7.Test result analysis:Here I analysed the no of patients on the basis of their results after treatment and found most of the patients was abnormal after treatment.I also filtered it on the basis of medication to know the condition of patients of specific diseases after treatment.

And in this way I finished my first excel project.

First week of learning data analytics.

Mohammad Meezan — Wed, 27 May 2026 14:45:29 +0000

1.Exact-Use to identify that is there any two identical data in two different strings.

2.Trim-Use to adjust text function in proper way inside a string.

3.Sort-Use to adjust the given set of numeric data in ascending order.

4.Text-Use to convert numeric data into textual data.

5.Value-Use to convert textual data into numeric data.

6.Concatenate-Use to merge two data in two different strings into one in a particular string

7.Upper-Use to convert textual data into capital letters.

8.Lower-Use to convert textual data into small letters.

9.Proper-Use to convert textual data in proper alphabetical way.

10.Len-Use to find the length of data in a string.

11.Right-Use to eliminate left portion of the data in a string.

12.Left-Use to eliminate right portion of the data in a string.

13.Today-Use to find the current date.

14 Now-Use to find current date and time.

15.Day-Use to find the date from Date/Month/Year.

16.Month-Use to find the month from Date/Month/Year.

17.Year-Use to find the year from Date/Month/Year.

18.Edate-Use to add month in Date/Month/Year.

19.Vlookup-Use to look for a certain value in the given table of the given data set.

Issues that I encountered while learning.
The first Issue that I faced while learning exact function.I was facing difficulty while implementing the exact function then I checked the formula where I mistakenly used colon symbol instead of coma symbol and my issue got fixed

=Exact(A1:A2) to =Exact(A1,A2)

The second issue I faced was while implementing vlookup function I was not able to get my desired value I got a value from different column,then I checked the formula and I mistakenly written the wrong column.Then I corrected my column index no and my issue got fixed.

My learnings
The most important thing I learned is to fill correct values inside the excel formula to get your desired result.