Live Interview of a Fresher | Power BI😲 | Answered 95% Questions ✔

so friends welcome back to our Channel learn with gigs in this video I have invited nitish Kumar who is an aspiring data analyst basically a fresher who is looking out for job in the powerbi role he is a potential fresher and you will see in the future he will definitely secure a job in this video I will be taking his powerb interview and I hope he performs very well so let's start the video and before that if you're new to the channel then do subscribe it and hit the Bell icon to stay updated with all the coming useful videos also you can follow me on Instagram learn with gigs where you will get regular job related updates as well as short videos on data analytics domain and friends do hit the like button of this video because your one like will give me the motivation to create more videos like this now let's head towards the interview hi NES how are you U I am fine how are you I'm also doing good so nitish U Can you briefly introduce yourself okay uh so my name is NES Kumar uh I am 2023 graduate I have a skills in powerbi SQL Python and Excel I have worked upon several personal projects in which I have utilized these tools to solve real world problems while working on these projects I have worked upon data extraction data cleaning data modeling data analysis and data visualization part so uh like how many projects you have built in power ba till now I have built four five uh I think I have built uh five reports till now okay and how many projects in SQL and python uh in SQL I have done two projects and in Python I have done one project which was of data extraction okay and any any Library you have covered in Python uh in Python I have worked upon pandas but I have some very basic skills on pandas like I have not gone in too much detail of pandas because I was able to do the similar kind of things using the SQL okay let's start with the first question so suppose uh you have three tables okay in power query okay and the structure of all those three tables are like similar to each other now you went ahead and appended those three tables okay M but okay so you have appended now now if you want to do the close and applyer so what will happen all those three initial tables plus that appended table containing the data of all those three tables will be loaded in powerb right yes but I don't want those three tables to be loaded I only want that appended table to be loaded in powerbi so how will you manage this uh so in power query we have option to uh we have option to enable load then from there we have to check that and then we will close and apply then uh only that particular merged query uh will be loaded into our powerbi data model right right right okay fine okay suppose you have one column okay and that column contains email ID of different people okay and that email ID is like this nitish docum gmail.com for example similarly other email IDs are there now if I want to extract the first part of that email ID for example nitish to create my name column which contains the first name then how will you extract that first name from that email ID column okay uh so in power query uh we have uh in I think in transform tab uh we have uh we have a option to split by delimeter then by using that split by delimeter we will be passing uh the delimeter on which we want to split the column and then we will we will be able to assl that column based upon that delimer okay uh fine do you know when when do we use have you used index uh column uh yes I have used index column so in what kind of scenario do we use index column uh uh in my in my case uh my table was not having a primary key and uh I wanted to establish a relationship between the between two tables uh so for that purpose I have uh I have uh created a index column in my Dimension table and and then uh created the relationship between both the tables using that index column okay suppose you want to check U like if there is any column in a table and you want to check how many distinct values that column contain okay so how can you check that in power query okay in power query in the inside the view tab we have a option to check column profile then in that uh after going into that tab we will just click on that particular column and then we will uh check on column quality or column profile then from uh then from that we will be able to get a summary of our column where we will be able to see how many distinct value our column is containing and how many total values our column is having if suppose that column contains around 20,000 records okay yes and you know that column profile will show only the top thousand like values right so according to that top thousand values it will tell what is the distinct and all so how can we like how can we see the overall distinct values if you have to see the overall 20,000 records of that column you know you know about this that we can we by default it shows top th yeah I know about this but I don't know like how I will be able to extract whole information about whole column fine no problem do you know like have you applied merge functionality in power query uh yes okay can you tell me what is merge uh basically uh it's similar to join in SQL okay so suppose uh we want to uh we want to uh create a master table based upon based upon some other table then in that case we want to join two tables so by using a common column between both the tables we can join we can create that master table so in merge we have options like left join right join left anti join inner join right anti join okay what is left anti join uh in left an join we will get only that record uh which are present in the left table uh we will basically we will get the unmatching record from left table means all the record which are only present in the left table but that is not present in the right table okay fine so how okay how do you differentiate uh that this table is a fact table or this table is a like Dimension table how do you differentiate that uh uh when we see uh when like in generally in fact table uh there are uh there are more number of data presents like there are more number of rows presents and if we see that uh there are some columns which are repeat which are repeating in the table then in that case we will consider that table as a fact table but what happens in in a dimension table datas are not repeated means uh we will be getting the data we will be getting only the distinct data means distinct rad we will be getting in the dimension table okay so if so you are saying that if data is repeated then it is a fact table if it is not then it's a dimension table this is what you saying yes and uh and fact table will be containing the uh uh quantitative data and uh Dimension table will be containing the qualitative data means Dimension table will be having information about any particular Dimension okay can you explain what is a snowflake schema uh in slope uh basically it's a version uh it's a version of it a version of a star schema in which dimension table is further normalized so suppose we have we have a dimension table called Product and inside that product table we have the sub cat of product then for every sub subcategory of the product product name is repeating then in that case what we will do we will create another time Dimension table which will be linked to our product table so this is the snowflake schema so you use the term normalization what is normalization uh basically normalization means uh uh it's a process uh it's a process to organize organize the data in our relational model in such a way that we reduce the data redundency okay what is cardinality cardinality means the card cardinality cardinality represents the relationship between two tables like how these two tables are related so this can be one to one many to many okay so ideally what kind of cardinality we should prefer uh ideally we should prefer uh one to many relationship okay so uh what kind of visuals you have used till now uh uh like bar graph stack bar uh stack bar chart and then scatter plot uh pie chart uh these kind of visuals I have used line chart okay like okay how will you differentiate a donut chart with a pie chart uh in pie chart uh we have uh we have the information present in the in the form of slices while in the donor chart we have the information present in the form of arcs and in the donor chart there is a hole in between and in pie chart there is no hole in between so basically the donor chart is just a variation of pie chart means it based upon requirement like what kind of visuals will be suited for our visualiz then in that case we prefer to use donut chart or pie chart okay how can you differentiate uh a measure with a calculated column uh measure is something uh which is evaluated only uh only during the run time so suppose we have created a measure then we drag and drop that measure into some particular visual then only at that time it will be executed and it will not be taking any extra amount of a space in our data model while calculated column will be calculated column will be created as a column inside our data model and it will be taking up a space in uh in our data model right okay suppose uh you have a slicer okay and that slicer is present on multiple Pages now if I if I select something in that slicer the same slicer is present in other pages also of the report so if I select something I want that selection should be visible in other pages of the report also so how it can be made possible uh there is option to sync slicers so if we enable that option then we will be able to do this thing okay fine uh what is the page level filter uh page level filter like if we apply any filter through filter pin and from that P if we have applied that filter for any particular page then that filter will be applied to only particular page and if we go to any other page then that then then that page will not be affected by this filter how have you set up drill through filter till now in any of your reports uh yes how do we how do we do that drill through uh uh firstly for drill through filter uh we must have a hierarchy of data like if we want to enable drill through for some date column then was then we must have a hierarchy of year then month and uh uh uh and then uh date uh and when we drag and drop that thing Auto on our visual then that will be automatically enabled our in our Visual and there is a fork like icon available in our Visual and if we click on that fork like icon then we will be able to drill through our visual do you know how to do uh how to set up a custom tool tip uh yes uh firstly we have to create a new page and in the canvas setting we have to set that page as a tool tip then for that page we have to enable tool tip and and on the page on on any particular visual for which we want to we want that tool tip to be visual so we have to link that tool tip to that particular visual then uh if we hover over that visual then we will be able to see that tool tip in our visual okay okay do you know about what if parameters uh no and do you know about field parameters no I have not worked on this thing f so what kind of Dax functions you have used till now uh like filter functions uh time intelligence function uh text function uh some table functions I have used this uh all these kind of functions Okay and like can you explain when do we use dates in Period function uh dates in Period so suppose if you want to get uh uh uh so you want me to uh tell like in What scenario we will use dates and period yeah yeah what like where it can be useful uh so generally when there is a need to calculate the running total or running average then in that scenario we will be using dates in Period okay and suppose you don't have a date table in your model so how can you create yourself date table uh so we have a function called calendar Auto index and if we use that function uh we will be able to create a uh a date table based upon the based upon the starting and end date like minimum and maximum date in our data model and how calendar Auto function is different from calendar function uh so in calendar function we have to pass the start date and end date but in calendar Auto function we do not have to pass the start date and end date it will automatically DET detect the minimum date uh which is present inside our data model and the maximum date which is present inside our data model and based upon that it will create the table automatically okay so Suppose there is a requirement and and I want a card visual on the page of the report and in that card visual I want to see the total sales of country India for example yes every time if the user opens that report in that card visual total sales of country India should be visible okay so how will you create a measure for that uh uh for this I think uh I have to use uh so so you are telling uh like by default if we open our power VI report then in that case if we select any country then then uh for that country it will be visible and uh no no no firstly first part is if if I open the report that visual card visual should show me the total sales of country India how will this be set up uh so for this uh we have to use calculate calculate function then inside the calate function uh as a filter modifier we have to we have to pass the country name as India there okay now the next part is if we also have a country slicer yes so by default it is showing India as you said but if I if I select some other country then it should show the sales of that particular country so now this how how you will set up this so for this we have to just uh we have to just do a little modification we have to use selected value so what the selected value will do uh if the context for column name uh uh filters down to just one column then it will return then it will return that value and then we will pass this inside a IF function and then we will pass the that that particular measure which will be calculating our value and then we will be able to get that thing okay how do the iterator functions work like uh the functions which ends with X how does it work so it basically goes rows by rows and then uh then applies the condition which we have written inside the iterator function and then according to that it gets the it gives the scalar value for each row okay uh what does filter function return uh filter function returns a subset of our table subset of our table so suppose we have applied some filter on our table uh then it will be returning a subset of table based upon the filter which we have applied okay is there any difference between date add and same period last year function uh date add and same period last year I do not think like I do not think there is any difference between the these two function because if we use this uh use these two functions to calculate the running total or moving average then in both the cases these two functions are uh giving the same real so if if you have if you have developed the report if you have to publish the report the powerb service right because ultimately we have to show the report to the end user so we have to publish that report to the powerb service so what kind of license as a developer you should have to do this uh we should have a pro license okay and and uh what is the premium license then uh premium license uh basically when an organization is having more than 10,000 user or or a certain number which is greater than 10,000 user then in that case we should be going for premium license because it is it will it will be economic economically viable for that company uh to get to use that premium license so if I say that nsh you have a premium license is this the statement right like as you said I can say to you that okay nitish you have a pro license you will say yes right yes but if I see to you do you have a premium license is it right uh there is a difference between Pro license and premium license suppose if you ask me uh that you have a pro license then I will say yes but when you ask me when you says to me do you have a premium license then in that case I will say no why because premium licensees ised to an organization rather than any individual person person so what organization does it gives the access to that premium license to its user okay do you know about uh contributor level access uh so if I say that you have a contributor level access so what can you do as a developer uh as a developer I can uh I can publish the report and I can assign a member I can assign a new user which will be having a access level lower than me okay so as a contributor you can do that yes are you sure about [Music] it have you actually worked on powerbi service like I just have theoretical knowledge on powerbi service I just use powerbi service to publish the report okay fine okay so you if you develop any kind of report you know that we have to set up a security right so firstly tell me what is RO level security and have you also set up any kind of R Security in your during the practicing part uh uh basically I have never used uh implemented Ro level security but but I just have some theoretical knowledge on Ro level security so it is just the different access level uh given to the users so suppose some users are located in Mumbai and or or some or or there is a team which works on sales and we want that team to just see the data about sales so in that case we will be using the RO level security to show that team just the data of sales and uh in Ro level security there are two types like one is a static and one is dynamic so in a static uh we each time we want to assign an access level to any particular user then we have to do it manually but what in static what in Dynamic Ro level security what we do uh we uh we create an Excel seat then in that Excel seat we give the filter column that filter column on which we want to give the access and then we give the user ID user ID or email ID of that person and then we connect that table uh we connect that uh newly created table uh to that table uh to the table to the data table and then uh when we want to give the access then in through powerbi service we just enter the email ID of that person then that person will be able to get the access uh according to uh his use okay fine okay what is uh a data Gateway do you know about data Gateway yes where it is useful so so suppose we have published our report on on powerbi service and we have on premise data set now the powerbi service needs to connect to any database to to filter out soose if we filter out our real through slicers then from somewhere it will be getting the data and then filtering the real so power VI Gateway is used to connect this powerbi service to our own premise data set right right okay nsh I'm done from my side uh I think uh you did really well uh most of the like I would say U more than 95% of the questions you said the right answer obviously from the powerb service side you don't have much exposure so we can expect that thing but other than that you have a good knowledge and you are really doing good so all the best because whatever you are doing just keep doing that and I think in the coming time you will definitely get a job as a fresher okay San thanks for your appreciation and I hope I will get a job soon

Channel: LearnWidGiggs

Views: 55,992

Keywords: power bi interview, power bi fresher interview, power bi interview live, power bi interview questions, power bi interview questions and answers, power bi interview questions and answers for freshers, power bi interview questions for freshers, interview questions for power bi developer, power bi interview for freshers, power bi mock interview for freshers, power bi live interview fresher, power bi basic interview questions for freshers, tcs power bi interview questions for freshers

Id: u7yAypveDRo

Length: 23min 28sec (1408 seconds)

Published: Mon Feb 05 2024