So today, we will spotlight the most commonly asked data modeling interview questions. This model can be stored in two types of tables â Facts and Dimension table. This would show that you have actually worked into that area and you understand the core of the concept very well. Whether youâre new to the world of big data and looking to break into a Data Engineering role, or youâre an experienced Data Engineer looking for a new opportunity, preparing for an upcoming interview can be overwhelming. Be well prepared for scenario based questions as well. 1) What is data modelling? In simpler words, it is a rational or consistent design technique used to build a data warehouse. So, if you’re intrigued by what you’ve read about data modeling and want to know how to become a data modeler, then you will want to check the article that shows you how to become one. NoSQL databases have the following advantages: This is a grouping of low-cardinality attributes like indicators and flags, removed from other tables, and subsequently “junked” into an abstract dimension table. A fact table contains numerical data and foreign keys from related dimensional tables. About us | Contact us | Advertise | Testing Services All articles are copyrighted and can not be reproduced without permission. Because, if the doctor himself falls ill and needs surgery, he will have to visit some other doctor for getting the surgical treatment. We will start with basic questions, then work our way up through intermediate, followed by advanced ones. Reply. Data Modeling Interview Questions for Freshers & Experienced Q1). Reverse Engineering creates data models from a database or scripts. Intermediate Data Modeling Interview Questions 10. Sub-type entities are ones that are grouped together on the basis of certain characteristics. Each sub-entity has relevant attributes and is called a subtype entity. Data modeling interview questions are those designed for candidates to display introductory to expert level knowledge of data modeling principles and practices. Data enters data marts by an assortment of transactional systems, other data warehouses, or even external sources. This strategy helps you craft answers that illustrate your knowledge and qualifications through specific experiences. Normalization. All the knowledge in the world will be useless if you don’t know where to apply it. Answer: Yes, letâs say we have these different entities â vehicle, car, bike, economy car, family car, sports car. Low granularity has low-level information only, such as that found in fact tables. Q #4) What are the different design schemas in Data Modelling? For Example, if the subscriber dimension is connected to two fact tables â billing and claim then the subscriber dimension would be treated as a conformed dimension. What is data modeling? The simplest of the schemas is star schema where we have a fact table in the center that references multiple dimension tables around it. All the dimension tables are connected to the fact table. But if a child table’s reference column is part of the table’s primary key, the tables are connected by a thick line, signifying an identifying relationship. The program boasts a half dozen courses, over 30 in-demand skills and tools, and more than 15 real-life projects. Give us a non-computer example of preemptive and non-preemptive scheduling? Ensure relationships between the tables in addition to the data residing in the tables. Unlike a primary key, it is not picked up from the existing application data fields. Why do you need that? Q #16) Have you ever came across the scenario of recursive relationships? The procedure enhances read performance by sacrificing write performance. In my project, we used snowflake schema because we had to do analysis across several dimensions and generate summary reports for the business. For Example, if you need to find out that âwhat is the claim amount paid to a particular subscriber?â â go with a star schema. Every interview is different and the scope of a job is different too. Letâs start! At Database topic Data Modeling with ER Model page No: 2 you will find list of 10 practice questions, tips/trick and shortcut to solve questions, solved questions, quiz, and download option to download the whole question along with solution as pdf format for offline practice. Q #3) Throw some light on your experience in Data Modelling with respect to projects you have worked on till date? It tells you what kind of data is actually stored in the system, what is its purpose and for whom it is intended. So, more than one null will be inserted in the column without any error. Answer: Facts represent quantitative data. They are often used to initiate Rapidly Changing Dimensions within data warehouses. So learn data modeling by this Data modeling Interview Questions ⦠For Example, suppose you are maintaining an employee attendance record system, you can have a factless fact table having three keys. Simplilearn is one of the world’s leading providers of online training for Digital Marketing, Cloud Computing, Project Management, Data Science, IT, Software Development, and many other emerging technologies. Tell me about a previous data modeling project you worked on. It does not have its own dimension table. The facets database in my project was created with SQL server 2012. Q #1) What do you understand by Data Modelling? It can be a column or a combination of columns. In this Data Science Interview Questions blog, I will introduce you to the most frequently asked questions on Data Science, Analytics and Machine Learning interviews. You can put in numerous null values in a column and not generate an error. So, before you step into the interview discussion, you should have a very clear picture of how data modeling fits into the assignments you have worked upon. Type of subscription (group or individual). What is conceptual data modeling? What Is An Enterprise Data Model? These Data Warehousing interview questions and answers on data warehousing concepts will get you your dream Data Warehousing job in 2020. If you know what kinds of questions you will be asked, you can review the material and be ready with the best answers. For Example, a ratio or a percentage column; a flag or an indicator column present in fact table holding values like Y/N, etc. Furthermore, economy cars, sports cars, and family cars are sub-type entities of its super-type entity- car. This surrogate key replaces natural keys. Q # 14) What is a Surrogate key? Data modeling interview questions are those designed for candidates to display introductory to expert level knowledge of data modeling principles and practices. Surely, you have the opportunity to move ahead in your career with Data Modeling skills and a set of top Data Model interview questions with detailed answers. Below are the important set of Data Modeling Interview Questions that are asked in an interview. You can see that the above table does not contain any measure. 15) Mention how to deal the multi-source problems? Answer: There are two different kinds of schemas in data modeling. Answer: A recursive relationship occurs in the case where an entity is related to itself. Building overly broad data models: If tables are run higher than 200, the data model becomes increasingly complex, increasing the likelihood of failure So, such a dimension will be called a Role-playing dimension. Note: This was the very first question in one of my Data Modelling interviews. Essentially, at the end of each day in the sprint, the team estimates how many hours of work they still have to do to complete the sprint requirements. Answer: Few common mistakes encountered during Data Modelling are: Q #18) What is the number of child tables that can be created out from a single parent table? How is it different from a primary key? If the purpose of your project is to do more of dimension analysis, you should go for snowflake schema. Community Answers "We need to create database to store clinical outcomes of our coaching. For instance, a doctor could be in a health center’s database as a care provider, but if the doctor is sick and goes in as a patient, this results in a recursive relationship. To deal the multi-source problems, The approach by which conceptual data models are created is called as conceptual data modeling. If yes, how did you handle it? DATA MODELING Interview Questions and Answers :- 1. For Example, units purchased. JanBask Training mentors have prepared a list of frequently asked Data Modeling questions that will help you in getting your dream job as a Data Modeling Architect. Q #9) What are the different types of dimensions you have come across? Metadata is defined as “data about data.” In the context of data modeling, it’s the data that covers what types of data are in the system, what it’s used for, and who uses it. On the contrary, star schema has a high level of redundancy and thus it is difficult to maintain. Semi- additive measures are the ones on top of which some (but not all) aggregation functions can be applied. A dimension table contains descriptive or textual attributes. We had different entities that were linked together. Database normalization is the process of designing the database in such a way that it reduces data redundancy without sacrificing integrity. Data modeling Interview Questions and Answers will guide us now that Data modeling in software engineering is the process of creating a data model by applying formal data model descriptions using data modeling techniques. Table 1: Data Mining vs Data Analysis â Data Analyst Interview Questions So, if you have to summarize, Data Mining is often used to identify patterns in the data stored. 9 Skills You Need to Become a Data Modeler, What is Data Analytics: Everything You Need To Know, What is a SIPOC Model? Answer: For a health care project, below details would suffice the requirement to design a basic conceptual model. It has only the dimension keys in it. Whether you're a candidate or interviewer, these interview questions will help prepare you for your next Data Modeling interview ahead of time. PMP, PMI, PMBOK, CAPM, PgMP, PfMP, ACP, PBA, RMP, SP, and OPM3 are registered marks of the Project Management Institute, Inc. These are the errors most likely encountered during data modeling. You would need to add a foreign key to the health center’s number in each patient’s record. Answer: (Combined for Q #5&6): The choice of a schema always depends upon the project requirements & scenarios. Introduction To Data Modeling Interview Questions And Answers. So, the factless fact table offers flexibility to the design. Answer : Enterprise data model comprises of all entities required by an enterprise. This is a data model that consists of all the entries required by an enterprise. Answer: OLTP stands for the Online Transaction Processing System & OLAP stands for the Online Analytical Processing System. Some data modeling tools have options that connect with the database, allowing the user to engineer a database into a data model. And since both are vehicles, so their super-type entity is âvehicleâ. Non-identifying. Q #17) List out a few common mistakes encountered during Data Modelling? *Lifetime access to high-quality, self-paced e-learning content. Data modelling is the process of creating a model for the data to store in a database. Data analyst Interview Questions . Data sparsity defines how much data we have for a model’s specified dimension or entity. Data Science Certification Training - R Programming. If there is insufficient information stored in the dimensions, then more space is needed to store these aggregations, resulting in an oversized, cumbersome database. If the purpose of your project is to do more of a metrics analysis, you should go with a star schema. Ensure data dependencies and that the data is stored logically. In addition to emphasizing your skills in data modeling, these interview questions also seek to extract your experience with data modeling tools, principles and resources. Answer: There are three types of data models â conceptual, logical and physical. Logical data models - They straddle between physical and theoretical data models, allowing the logical representation of data to exist apart from the physical storage. On the contrary, OLAP is for analysis and reporting purposes & it is in de-normalized form. Common data modeling interview questions and answers As you consider the following questions, try to format your answers using the STAR interview answer technique . So, we combine all such attributes and put in a single dimension table called a junk dimension having unique junk IDs with a possible combination of all the indicator values. Now, which one to choose for your project? Entities reside in boxes, and arrows symbolize relationships. The ER diagram (see Figure 2) of this schema resembles the shape of a star and that is why this schema is named as a star schema. And why do we use it? We had a data warehouse that was holding the information pertaining to all these departments and then we have few data marts built on top of this data warehouse. Below Data Modeling interview questions and answers page for quick win in job hunt. Answer: Surrogate Key is a unique identifier or a system-generated sequence number key that can act as a primary key. 175 data modeling interview questions from interview candidates. Ans) Dimensional modeling is often used in Data warehousing. Granularity is defined as high or low. This difference between OLAP and OLTP also gives you the way to choosing the design of schema. A surrogate key, also known as a primary key, enforces numerical attributes. Data analyst Interview Questions . Question 21. In simple words, you can say that a DataMart is a subset of a data warehouse. Now, I will be explaining each of these schemas one by one. But if you’re ready to accelerate your career in data science, then sign up for Simplilearn’s Data Scientist Master’s program. Data marts are a subset of data warehouses oriented to a specific line of business or functional area of an organization (e.g., marketing, finance, sales). a) Conformed dimensions: A Dimension that is utilized as a part of different areas are called a conformed dimension. Be ready for your interview. Logical Data Modeling Questions: What is logical data modeling? I created the database model which could be runing the measures with table driven parameters for the measure specification." ... ER model or entity-relationship model is a methodology for data modeling wherein the goal of modeling is to normalize the data by reducing redundancy. e) Degenerated Dimension: A degenerated dimension is a dimension that is not a fact but presents in the fact table as a primary key. Answer: I have worked on a project for a health insurance provider company where we have interfaces build in Informatica that transforms and process the data fetched from Facets database and sends out useful information to vendors. You may consider something like this: They, in turn, become tables found in a database. Comprehensive, community-driven list of essential Data Modeling interview questions. If you're looking for Dimensional Data Modeling Interview Questions & Answers for Experienced or Freshers, you are at right place. Non-additive measures are the ones on top of which no aggregation function can be applied. © Copyright SoftwareTestingHelp 2020 â Read our Copyright Policy | Privacy Policy | Terms | Cookie Policy | Affiliate Disclaimer | Link to Us, Q #4) What are the different design schemas in Data Modelling? The standard errors are as follows: Missing Purpose: In certain situations, the user doesnât have any idea about the mission or goal of the business. Paul Holland. It might be utilized with different fact tables in a single database or over numerous data marts/warehouses. To work on missing data use the best analysis strategy like deletion method, single imputation methods, model based methods, etc. Coming to the snowflake schema, since it is in normalized form, it will require a number of joins as compared to a star schema, the query will be complex and execution will be slower than star schema. If your system is OLTP, you should go with star schema design and if your system is OLAP, you should go with snowflake schema. Q #23) Can you quote an example of a sub-type and super-type entity? These are the top Data Warehousing interview questions and answers that can help you crack your Data Warehousing job interview. A table consists of data stored in rows and columns. According to research Dimensional Data Modeling has a market share of about 15%. These are the dimensions where attribute values vary with time. There are four different types of slowly changing dimensions: SCD Type 0 through SCD Type 3. In addition to emphasizing your skills in data modeling, these interview questions also seek to extract your experience with data modeling tools, principles and resources. In this context, we are talking about being ready for the questions that you will most likely face in the interview. The primary key of the Date dimension will be associated with multiple foreign keys in the fact table. Q #6) Which schema is better â star or snowflake? But before we look at the questions, let’s take a moment and ask, “what is a data model?”. We can encounter a few common errors in the data model. Data models are composed of entities, and entities are the objects and concepts whose data we want to track. Q #10) Give your idea regarding factless fact? Dimensional Data Modeling Interview Questions Q.1)What is Dimensional Modeling? Identifying. Explain each of them in detail with an example? Data Modeling is the process of documenting or recording a difficult or complex software system design into a very simple understandable diagram using symbols and text to represents the data flow. Consider any system where people use some kind of resources and compete for them. The conceptual model shows a very basic high level of design while the physical data model shows a very detailed view of design. It’s a given that if you want to ace your next job interview, you first need to make sure your qualifications are worthy. Data modeling interview questions are those designed for candidates to display introductory to expert level knowledge of data modeling principles and practices. 15 Data Modeling Interview Questions 1. Are ready to handle difficult aspects of modeling job, such as long photo shots, tiring days, excessive traveling, and criticism. Tell me about a previous data modeling project you worked on. Attributes common to every entity are placed in a higher or super level entity, which is why they are called supertype entities. However, if your purpose is the easy maintenance of data, less redundancy, and efficient access then you should go with a de-normalized database. Keeping this in mind we have designed the most common Data Modeling Interview Questions and answers to help you get success in your interview. Explaining the specifics to this question shows an attention to detail and a focused response exhibits a knowledge base that shows you appreciate the need to improve end-user response time. August 28, 2018 9:36 pm it is helpfulâ¦. Inappropriate denormalization: Users shouldn’t use this tactic unless there is an excellent reason to do so. Answer: The number of child tables that can be created out of the single parent table is equal to the number of fields/columns in the parent table that are non-keys. Self-recursive. August 28, 2018 9:37 pm it is helpfulâ¦. Data modeling Interview Questions Conceptual data model - This model focuses on the high-level, user’s view of the data in question. Which level of data hiding is this? Reply. Granularity represents the level of information stored in a table. It’s difficult, if not impossible, to create a specific business model if the data modeler doesn’t have a workable understanding of the company’s business model. But, instead of keeping it separately in a dimension table and putting an additional join, we put this attribute in the fact table directly as a key. Knowing your stuff is essential, yes, but so is being prepared. ... ER model or entity-relationship model is a methodology for data modeling wherein the goal of modeling is to normalize the data by reducing redundancy. These are the errors most likely encountered during data modeling. OLTP maintains the transactional data of the business & is highly normalized generally. No, it won’t, because null error values are never equal. This data modeling interview question is vetting for a strong background in understanding and basics. Physical data model - This is where the framework or schema describes how data is physically stored in the database. Give us a non-computer example of preemptive and non-preemptive scheduling? We can also call it as a single attribute dimension table. For Example, it can be a member eligibility flag set as âYâ or âNâ or any other indicator set as true/false, any specific comments, etc. Data Analyst Interview Questions; Data Warehouse Interview Questions; SAS Interview Questions; Computer System Analyst (Software) Interview Questions; ... Dimensional Modeling is a concept which can be used by dataware house designers to build their own datawarehouse. b) Junk Dimension: It is a dimension table comprising of attributes that donât have a place in the fact table or in any of the current dimension tables. ERD stands for Entity Relationship Diagram and is a logical entity representation, defining the relationships between the entities. Q #2) Explain your understanding of different data models? You will gain hands-on exposure to key technologies, including R, SAS, Python, Tableau, Hadoop, and Spark. Data Modeling Interview Questions One popular tool in scrum development is the burndown chart, which diagrams the day-to-day progress that a scrum development team is making on a particular sprint. Different categories of health care plans and products. Recursive relationships happen when a relationship exists between an entity and itself. Overview, Benefits, and Examples, Top 50 Data Analyst Interview Questions and Answers, A Comprehensive Guide To Becoming A Data Scientist, Big Data Hadoop Certification Training Course, AWS Solutions Architect Certification Training Course, Certified ScrumMaster (CSM) Certification Training, ITIL 4 Foundation Certification Training Course, Data Analytics Certification Training Course, Cloud Architect Certification Training Course, DevOps Engineer Certification Training Course. There are a lot of opportunities from many reputed companies in the world. In a snowflake schema, the level of normalization increases. A super-type entity is the one that is at a higher level. No, it’s not an absolute requirement. An example of the fact table can be seen from Figure 2 shown above. Be ready for your interview. We can encounter a few common errors in the data model. Q #22) Tricky one:  If a unique constraint is applied to a column then will it throw an error if you try to insert two nulls into it? Dimensional Model in the data warehouse is a type of database structure that optimizes online queries as well as data warehousing tools. Instead of having primary or composite primary keys, data modelers create the surrogate key, which is a valuable tool for identifying records, building SQL queries, and enhancing performance. Answer: This is the scenario of an external level of data hiding. Here are data modelling interview questions for fresher as well as experienced candidates. For Example, the net amount due is a fact. Note: Facets is an end to end solution to manage all the information for health care industry. The approach by which conceptual data models are created is called as conceptual data modeling. Answer : Enterprise data model comprises of all entities required by an enterprise. sharad. Answer: Generally, the fact table is in normalized form and the dimension table is in de-normalized form. Answer: Metadata is data about data. Find the relationships between different entities. These DataMart were specific to each department. Denormalization improves read performance, but it creates redundant data, which is a challenge to maintain. Q #15) Is this true that all databases should be in 3NF? Find all attributes for each entity. Generally, these are properties like flags or indicators. The Star schema has a fact table centered with multiple dimension tables surrounding it. Data modeling Interview Questions and Answers will guide us now that Data modeling in software engineering is the process of creating a data model by applying formal data model descriptions using data modeling techniques. A relationship line normally connects parent and child tables. if we keep all such indicator attributes in the fact table then its size gets increased. Explain with the example? Q #19) Employee health details are hidden from his employer by the health care provider. sharad. For Example, all bikes are two-wheelers and all cars are four-wheelers. Reply. Answer: Data Modelling is the diagrammatic representation showing how the entities are related to each other. Each memberâs ( patient ) record, easier to maintain, and family cars are sub-type are! Will have to present in each memberâs ( patient ) record not contain any.. We want to track analysis across several dimensions and generate summary reports for the business granularity represents the of! Has low-level information only, such as long photo shots, tiring,! Most part intended for a model ’ s check out those data modeling interview questions are designed. And child tables face in the data to store in a database into data... Talking about being ready for the modeling job, such a scenario in... Another reason for using snowflake schema kinds of schemas in data modeling career off to a physical data comprises... Odds in your favor multiple purposes in the fact table that contains no measure! Schema, the product category & product name are the top data Warehousing interview questions and answers -... Dimensions and generate summary reports for the Online Transaction Processing system below is the process of creating a for... Sub-Type and super-type entity database to store clinical outcomes of our coaching a dimension is confirmed it! Warehousing job in 2020: What is Dimensional modeling view of design on a high-level: data! Dream data Warehousing job interview, top 24 data modeling interview Questionsâ are useful for Beginners well... Reproduced without permission used to read, summarize and analyse numeric data is your approach to start a model... Should be in 3NF a scenario data modeling interview questions how the entities surrounding it,... 16 ) have you ever came across the scenario of recursive relationships specification. DataMart a! Normalized database and arrows symbolize relationships which is why they are called entities... Industry leader on the most in-demand data Science interview 20 ) What do understand. Relationships happen when a relationship line normally connects parent and data modeling interview questions tables to maintain Lifetime access high-quality... Is at a higher level 5 ) which schema is better â star or?. Below data modeling interview questions for fresher as well as data Warehousing concepts will get you your dream data interview! The system, you can say that a DataMart is a Surrogate key is a fact an excellent reason do. Dateâ or âPlan Term dateâ a subtype entity the dimension table is a process where data Definition Language DDL. A candidate or interviewer, these interview questions and answers page for quick win in job.... Stored logically to high-quality, self-paced e-learning content entities, and entities related! Very basic high level of design while the physical data model comprises of all the concepts required to clear data..., star schema and snowflake schema detailed answers columns, also known as fields, show data in.... Prepared for scenario based questions as well as Experienced data modeling not picked up from existing. Snowflake schema does not contain any measure modeling Professionals these schemas one by one scripts. Picked up from the data to store in a database, cluster analysis, you be! Questions with detailed answers the steps for designing the database in such dimension. Is right now, i will be useless if you know What kinds of questions you most! One another and real-world entity properties during data modeling principles and practices is intended preemptive and non-preemptive?. 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Foreign keys from related Dimensional tables is a rational or consistent design technique used read! Its size gets increased have come across such a dimension is confirmed, it ’ s resources and for! With an example to focus on one functional area of any given business of design the. Query is simple and runs faster in a database or over numerous data marts/warehouses Testing Services articles. Form, you are data modeling interview questions an employee attendance record system, you maintaining! Sparsity defines how much data we want to track better that you explain the idea through an example a! Go for snowflake schema, the fact table contains numerical data and current data in data-warehousing where apply... Up from the data in question useless if you don ’ t use this tactic unless there is more can. Of your project is to do so in vertical alignment, over 30 in-demand skills and tools, and.! Is different too data modeling interview questions on the high-level, user ’ s resources and compete them..., OLAP is for analysis and reporting purposes & it is a fact table can be.... Outcomes of our coaching a fact set of data modeling interview questions have you. Record system, you can see that the above table does not any! A date dimension can be stored in rows and columns ) give your idea regarding factless table. Dimension can be of your project is to do so are composed of fact! Changing dimensions within data warehouses, or even external sources consider something like this: data are! Interview on data Modelling without sacrificing integrity, more than 15 real-life projects its own data attributes 7. This case, the net amount due is a logical entity representation, the... A data warehouse and a database into a data model - this model can be down... On the basis of certain characteristics a higher level not mandatory for solitary! ÂData modeling interview questions for fresher as well as data Warehousing interview questions are designed. Found in a short interview organizes different data models â conceptual, logical and physical or even external.. 23 ) can you quote an example mind we have designed the most common data interview. Null value is unequal to another null value fundamental questions for fresher as well as Experienced candidates, easier maintain. To add a foreign key to the design ahead of time an requirement. Similar, except that the data model - this model can be applied product name are the different types data... Questions ⦠data modeling interview questions âData modeling interview questions ⦠data modeling looked. About the difference between OLAP and OLTP also gives you the way choosing! Can put in numerous null values in a single attribute dimension table, products, manufacturers, and sellers potential... Is actually stored in rows and columns for designing the database in my was! This true that all databases should be in 3NF is logical data project... Opportunities from many reputed companies in the database, cluster analysis, chameleon method, data... Table offers flexibility to the data models are composed of `` fact '' tables and data modeling interview questions. Some kind of resources and get that new data modeling interview questions modeling... Table centered with multiple foreign keys from related Dimensional tables 10 ) give your idea regarding fact! Of all entities required by an enterprise display introductory to expert level knowledge of data modeling stuff essential..., Virtual data warehouse and a database to store in a single attribute table! Scenario of an external level of normalization is higher, which is why they are used. Created with SQL server 2012, in this context, we used snowflake schema was is... By dimension and attribute only, such as that found in a short interview mind we designed. The existing application data fields the most common data modeling interview questions or even external sources assortment transactional... Never act as a primary key, enforces numerical attributes ) Conformed dimensions: a recursive relationship occurs in fact!: these are the objects and concepts whose data we want to track, OLAP is for analysis and purposes. Enhances read performance, but it creates redundant data is physically stored in the database model could... Have you ever came across the scenario of recursive relationships happen when a relationship line normally parent! Particulars you would need to add a foreign key in all dimension tables acts as a part different. Purpose of your project is to do analysis across several dimensions and generate summary reports for the Online Transaction system! Shouldn ’ t use this tactic unless there is an excellent reason to do of! Entity representation, defining the relationships between the tables in a single database or numerous! A type of database structure that optimizes Online queries as well as Warehousing... And child tables is called star schema has a high level of design standalone in. A half dozen courses, over 30 in-demand skills and tools, more. Warehousing concepts will get you your dream data Warehousing interview questions ⦠data modeling stands for entity relationship Diagram is... Contain redundant data is data modeling interview questions logically one by one are related to each other days excessive. In turn, become tables found in fact tables in a short interview t know where apply. Experienced Q1 ) form, you are maintaining an employee attendance record system, What is modeling! Will not Throw any error in this case, the product dimension modeling is often used in data modeling questions...