Note: This course will be updated … It is a conceptual representation of data objects, the association between different data objects, and the rules. If you want to become a Certified Data Modeling Specialist, then visit Mindmajix - A Global online training platform: “Data Modeling Training”. In fact, interviewers will also challenge you with brainteasers, behavioral, and situational questions. ; These Data Modeling Interview Questions are useful for Beginners as well as Experienced Data Modeling Professionals. Now, I will be explaining each of these schemas one by one. Denormalization is done in dimensional data modelling used to construct a data ware house. His passion lies in writing articles on the most popular IT platforms including Machine learning, DevOps, Data Science, Artificial Intelligence, RPA, Deep Learning, and so on. 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. We make learning - easy, affordable, and value generating. The level of complexity and detail increases from conceptual to logical to a physical data model. The example for preemptive scheduling is people standing in queue for tickets. But there is more you can do to help weigh the odds in your favor. The fact table here remains the same as in star schema. The query is simple and runs faster in a star schema. Below mentioned are the Top Frequently asked Data Modeling Interview Questions and Answers that will help you to prepare for the Data Modeling interview. Ans: The conceptual data model includes all major entities and relationships and does not contain much detailed level of information about attributes and is often used in the initial planning phase. Either you can create a logical data model Metadata of physical model Metadata. Ans: First normal form, Second normal form, third normal forms are three types of normalization used in practice. Helping our community since 2006! Q #5) Which scheme did you use in your project & why? Ans: E.F. Codd gave some rules to design relational databases and the rules were focused on removing data redundancy which helps to overcome normal data modeling problems. Additive measures are the ones on top of which all aggregation functions can be applied. This field has a lot for the potential seekers and the individuals interested in the visualization in software engineering. Q45). Ans: A logical data model is the version of a data model that represents the business requirements (entire or part of an organization). What is an artificial (derived) primary key? For Example, fee rate or account balance. For 3NF, first, the table must be in 2NF, plus, we want to make sure that the non-key fields are dependent upon ONLY the PK, and not other non-key fields for its existence. Answer: We have three types of measures, namely. So, in this case, the entity – health care provider is related to itself. Q4). Q #20) What is the form of fact table & dimension table? Answer: (Combined for Q #5&6): The choice of a schema always depends upon the project requirements & scenarios. Ans: An entity is in the second normal form if all of its attributes depend on the whole (primary) key. Q #10) Give your idea regarding factless fact? Ans: Physical data model includes all required tables, columns, relationship, database properties for the physical implementation of databases. Example: social security number, bank account number, bank routing number. In my project, we used snowflake schema because we had to do analysis across several dimensions and generate summary reports for the business. Dimensional Data Modeling Interview Questions Q.1)What is Dimensional Modeling? Ans: Logical Data Model: Entity, Attributes, Super Type, Sub Type, Primary Key, Alternate Key, Inversion Key Entry, Rule, Relationship, Definition, business rule, etcPhysical Data Model: Table, Column, Primary key Constraint, Unique Constraint or Unique Index, Non Unique Index, Check Constraint, Default Value, Foreign Key, comment etc. Why are recursive relationships are bad? A recursive relationship occurs when there is a relationship between an entity and itself. What is the difference between a logical and physical data model? A derived key is an artificial key that you create. The approach by which data models are created is called as data modeling. The important or main object in a database is a table which consists or rows and columns. Ans: The visual representation of objects in a relational database (usually a normalized) is called as relational data modeling. Data Modeling Tools have options to create reports by checking various options. Be well prepared for scenario based questions as well. Q #23) Can you quote an example of a sub-type and super-type entity? Answer: Factless fact table is a fact table that contains no fact measure in it. Note: This was the very first question in one of my Data Modelling interviews. Q20). Q36). e) Degenerated Dimension: A degenerated dimension is a dimension that is not a fact but presents in the fact table as a primary key. This would show that you have actually worked into that area and you understand the core of the concept very well. There are lot of opportunities from many reputed companies in the world. So, such a dimension will be called a Role-playing dimension. These DataMart were specific to each department. This course will help you to achieve excellence in this domain. UML interview questions: UML (Unified Modeling Language) has been spreading its roots among the designing and visualization part. This is not usually done for data bases of transactional systems. Q #1) What do you understand by Data Modelling? Yes, I have come across such a scenario. It  would be good if the physical data modeler knows about replication, clustering and so on. Q16). Q #11) Distinguish between OLTP and OLAP? Let’s start! Q #17) List out a few common mistakes encountered during Data Modelling? Whether you’re new to the world of big data and looking to break into a Data Engineering role, or you’re an experienced Data Engineer looking for a new opportunity, preparing for an upcoming interview can be overwhelming. Top 24 Data Modeling Interview Questions with Detailed Answers. About us | Contact us | Advertise | Testing Services All articles are copyrighted and can not be reproduced without permission. 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. In SQL terms, the third normal form means that no column within a table is dependent on a descriptor column that, in turn, depends on the primary key. Answer: This is the scenario of an external level of data hiding. Parent table and child table are connected by a relationship line. The non-computer examples for preemptive scheduling the traffic on the single lane road if there is emergency or there is an ambulance on the road the other vehicles give path to the vehicles that are in need. Parent table and child table are connected by a relationship line. Ans: A data model is a conceptual representation of business requirement (logical data model) or database objects (physical) required for a database and are very powerful in expressing and communicating the business requirements and database objects. If yes, how did you handle it? Since star schema is in de-normalized form, you require fewer joins for a query. Answer: Dimensions represent qualitative data. Copyright © 2020 Mindmajix Technologies Inc. All Rights Reserved. Ans: The primary key constraint is imposed on the column data to avoid null values and duplicate values. 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? 250+ Data Modeling Interview Questions and Answers, Question1: What is data modeling? They also set the stage for the design of databases later on in the SDLC.There are three basic elements in ER models:Entities are the “things” about which we seek information.Attributes are the data we collect about the entities.Relationships provide the structure needed to draw information from multiple entities. trainers around the globe. customizable courses, self paced videos, on-the-job support, and job assistance. Data Modeling Interview Question 1.What do you understand by data modeling? Erwin Data Modeling Tool Interview Questions and Answers. And these dimension tables are linked by primary, foreign key relation. It might be utilized with different fact tables in a single database or over numerous data marts/warehouses. If the purpose of your project is to do more of dimension analysis, you should go for snowflake schema. a) Conformed dimensions: A Dimension that is utilized as a part of different areas are called a conformed dimension. A fact table contains numerical data and foreign keys from related dimensional tables. Ravindra Savaram is a Content Lead at Mindmajix.com. Give us a non-computer example of preemptive and non-preemptive scheduling? The attribute is a function of the column. Question2: What does data model contain? Q31). 1. About SoftwareTestingHelp. Data architect interview questions don’t just revolve around role-specific topics, such as data warehouse solutions, ETL, and data modeling. Ans: Using a name as the primary key violates the principle of stability. Introduction To Data Modeling Interview Questions And Answers. You are here: Home / Latest Articles / Data Analytics & Business Intelligence / Top 30 Data Analyst Interview Questions & Answers last updated October 3, 2020 / 3 Comments / in Data Analytics & Business Intelligence / by renish After all, we know that the relationship to the PK is good, because we established that in 2NF. Top 30 SAS Interview Questions and Answers. If yes ,then what’s the advantage of a Hashed File stage over sequential filestageSearch is faster in hash files as you can directly get the address of record directly by hash algorithm as records are stored like that but in case of sequential file u must compare all the records. Q #7) What do you understand by dimension and attribute? Q5). 30+ TOP Data Modelling Interview Questions and Answers Data Modelling Interview Questions. The approach by which logical data models are created is called as logical data modeling. This is the actual implementation and extension of a conceptual data model. Answer: OLTP stands for the Online Transaction Processing System & OLAP stands for the Online Analytical Processing System. A foreign key to the health insurance provider’s number will have to present in each member’s (patient) record. Functional dependency indicates that a link exists between the values in two different columns. If the referenced column in the child table is a part of the primary key in the child table, relationship is drawn by thick lines by connecting these two tables, which is called as identifying relationship. Because of the more complex nature of these relationships, we will need slightly more complex methods of mapping them to a schema and displaying them in a style sheet. A super-type entity is the one that is at a higher level. Is this statement TRUE or FALSE? If the attribute also depends on other columns, they must be columns of a candidate key; that is, columns that are unique in every row. Most popular portal for Software professionals with 100 million+ visits and 300,000+ followers! Attributes are the data we collect about the entities. Q #1) What do you understand by Data Modelling? What is data sparsity and how it effect on aggregation? Ans: Check constraint is used to check range of values in a column. Table contains rows and columns. What is reverse engineering in a data model? Q15). The approach by which conceptual data models are created is called as conceptual data modeling. Before moving ahead, you may go through the recording of Data Science Interview Questions where our instructor has shared his experience and expertise that will help you to crack any Data Science. This is very similar to to 2NF, except that now you are comparing the non-key fields to OTHER non-key fields. Tell us something about the surrogate key. Sadly, I was told the position was for Data engineer-3 and that I was suitable only for Data Engineer-2 but also that I had to wait for a year and give the interview again. For Example, a data attribute of the provider will be provider identification number, few data attributes of the membership will be subscriber ID, member ID, one of the data attribute of claim will claim ID, each healthcare product or plan will be having a unique product ID and so on. 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. The attributes which are common to these entities are moved to a super (higher) level entity, which is called as supertype entity. Data modeling is a diagrammatic representation. And fact tables primary is the union of its all dimension table key. Explain with the example? Ans: Unique constraint is imposed on the column data to avoid duplicate values, but it will contain NULL values. Ans: Forward Engineering is a process by which DDL scripts are generated from the data model. A data base can also be created without normalization. Ans: Star Schema: Well in star schema you just enter your desired facts and all the primary keys of your dimensional tables in Fact table. Now, if you want to answer the below question, you can do easily using the above single factless fact table rather than having two separate fact tables: “How many employees of a particular department were present on a particular day?”. The employee entity is related to itself, and there is a one-to-many relationship between one employee (the manager) and many other employees (the people who report to the manager). An example of the fact table can be seen from Figure 2 shown above. Question 21. 1) What is data modelling? For Example, if you need to find out that “what is the claim amount paid to a particular subscriber?” – go with a star schema. So, You still have opportunity to move ahead in your career in Data Modeling Architecture. If the purpose of your project is to do more of a metrics analysis, you should go with a star schema. Consider any system where people use some kind of resources and compete for them. Data Modeling Interview Questions Enroll in Course for $27. Had 6 rounds. We fulfill your skill based career aspirations and needs with wide range of Instead of having primary key or composite primary keys, the data modelers create a surrogate key; this is very useful for creating SQL queries, uniquely identify a record and good performance. 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. Data modeling interview questions are those designed for candidates to display introductory to expert level knowledge of data modeling principles and practices. Q24). Ans: An entity is in the third normal form if it is in the second normal form and all of its attributes are not transitively dependent on the primary key. The social security number might be a valid choice, but a foreign employee might not have a social security number. In a database, high cardinality means more unique values are stored in a column and vice versa. ; Data Modeling Interview Questions: What is a subtype and supertype entity? Answer: There are two different kinds of schemas in data modeling. It has only the dimension keys in it. It’s a given that if you want to ace your next job interview, you first need to make sure your qualifications are worthy. We first create the conceptual model, then the logical model and finally move to the physical model. According to research Dimensional Data Modeling has a market share of about 15%. And since both are vehicles, so their super-type entity is ‘vehicle’. What is data modeling? What is a conceptual data model and conceptual data modeling? How many null values can be inserted in a column that has a unique constraint? Ans: In normal practice, a numerical attribute is enforced a primary key which is called as surrogate key. What is ER (entity relationship) diagram or ERD? Below question-answers can be of your great help if you get a chance to face or take an interview on Data Modelling. So, the factless fact table offers flexibility to the design. Very simple technical questions. It is the initial step towards database design. Let's have a look into them. c) Role-Playing Dimension: These are the dimensions that are utilized for multiple purposes in the same database. Answer: For a health care project, below details would suffice the requirement to design a basic conceptual model. For Example, it can be a member eligibility flag set as ‘Y’ or ‘N’ or any other indicator set as true/false, any specific comments, etc. The primary key in all dimension tables acts as a foreign key in the fact table. If you do not convert your model to the second normal form, you risk data redundancy and difficulty in changing data. These entities are called subtype entities. However, the dimension tables are normalized. Ans: Index is imposed on a column or set of columns for fastest retrieval of data. When should you consider denormalization? Q #4) What are the different design schemas in Data Modelling? Statistics Interview Questions. However, if your purpose is the easy maintenance of data, less redundancy, and efficient access then you should go with a de-normalized database. It tells you what kind of data is actually stored in the system, what is its purpose and for whom it is intended. If the value of an attribute depends on a column, the value of the attribute must change if the value in the column changes. Data Analysis Interview Questions and Answers. Q39). Data Modeling Interview Questions: In the blog, you have to learn the list of frequently asked Data Modeling interview questions and answers for freshers and experienced professionals. I think all this added focus on data has given us a ripe opportunity to help our business organizations to leverage data modeling and other data management approaches even more than ever. Ans) Dimensional modeling is often used in Data warehousing. Q14). Sub-type entities are ones that are grouped together on the basis of certain characteristics. Logical Data Models contain Entity, Attributes, Super Type, Sub Type, Primary Key, Alternate Key, Inversion Key Entry, Rule, Relationship, Definition etc. SQL and Data modeling related. Q11). A natural key is one that is already part of the database. You will absolutely love our tutorials on QA Testing, Development, … Data now resides in main-memory (RAM) and no longer on a hard disk. Data Ware house and Data Mart Interview Questions and Answers. Frequently Asked Data Modeling Interview Questions - [Updated 2020]. How is it different from a primary key? Answer: Surrogate Key is a unique identifier or a system-generated sequence number key that can act as a primary key. Ans: A standalone column in a table will be connected to the primary key of the same table, which is called as recursive relationship. Every interview is different and the scope of a job is different too. In star schema dimensional tables are usually not in BCNF form. Ans: A data model is a conceptual representation of business requirement (logical data model) or database objects (physical) required for a database and are very powerful in expressing and communicating the business requirements and database objects. Below is the conceptual Data Model showing how the project looked like on a high-level. Explore Data Modeling Sample Resumes! Generally, the data models are created in data analysis & design phase of software development life cycle. Transitive dependence means that descriptor key attributes depend not only on the whole primary key, but also on other descriptor key attributes that, in turn, depend on the primary key. It does not have its own dimension table. d) Slowly Changing Dimension (SCD): These are most important amongst all the dimensions. Data analyst Interview Questions . In a snowflake schema, the level of normalization increases. What are the important types of Relationships in a data model. Q #9) What are the different types of dimensions you have come across? For Example, a ratio or a percentage column; a flag or an indicator column present in fact table holding values like Y/N, etc. If you want to become a Certified Data Modeling Specialist, then visit Mindmajix - A Global online training platform: This course will help you to achieve excellence in this domain. Explain with the, 10 Best Data Modeling Tools To Manage Complex Designs, Top 24 Data Modeling Interview Questions with Detailed Answers. What is a composite foreign key constraint? Q9). The following explanations make this more specific: If the table has a one-column primary key, the attribute must depend on that key.If the table has a composite primary key, the attribute must depend on the values in all its columns taken as a whole, not on one or some of them. Ans: Recursive relationships are an interesting and more complex concept than the relationships you have seen in the previous chapters, such as a one-to-one, one-to-many, and many-to-many. Conceptual, physical or external? We can also call it as a single attribute dimension table. Now, which one to choose for your project? Q38). 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. Dimensional Data Modeling Interview Questions and Answers. Ans: Column also known as field is a vertical alignment of the data and contains related information to that column. What is a composite primary key constraint? OLTP maintains the transactional data of the business & is highly normalized generally. A dimension table contains descriptive or textual attributes. Automic values:- The Single cell have only single value When a numerical attribute is enforced on a primary key in a table, it is called the surrogate key. Oracle Database Fundamentals Interview Questions and Answers . Ans: One to One, One to many, and many to many are different types of cardinalities. Advanced-Data Modeling Interview Questions. You can stay up to date on all these technologies by following him on LinkedIn and Twitter. They are designed for the individual departments. Database performance, indexing strategy, and physical storage are important parameters of a physical model. At times, certain situations may arise in the business where you need to have a factless fact table. Data Modeling Interview Questions And Answers Global Guideline . Example: all online transactions, bank transactions, trading transactions. Heck, data management even made it into the US State of the Union Address. Ans: Many null values can be inserted in an unique constraint column because one null value is not equal to another null value. 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. The data about various objects in the data model is called as data model Metadata. It is the initial step towards database design. Ans: Usually, in a data model, parent tables and child tables are present. If your system is OLTP, you should go with star schema design and if your system is OLAP, you should go with snowflake schema. If you're looking for Dimensional Data Modeling Interview Questions & Answers for Experienced or Freshers, you are at right place. So learn data modeling by this Data modeling Interview Questions with Answers guide . What is a physical data model and physical data modeling? Ans: ER diagram is a visual representation of entities and the relationships between them. Q #24) What is the significance of metadata? COM design of databases later on in the SDLC. What are the important types of Relationships in a data model? Surrogate key is a substitute for natural keys. You are here: Home / Latest Articles / Data Analytics & Business Intelligence / Top 50 Data Warehouse Interview Questions & Answers last updated October 3, 2020 / 4 Comments / in Data Analytics & Business Intelligence / by admin Data modeling tools have options to connect to the database by which we can reverse engineer a database into a data model. Answer: Data Modelling is the diagrammatic representation showing how the entities are related to each other. The primary key of the Date dimension will be associated with multiple foreign keys in the fact table. 2) Explain various types of data models. Download & Edit, Get Noticed by Top Employers! Interview questions for SAP-HANA Data Modelling General Questions: 1.What is SAP-HANA?. So, how do you prepare for a successful data architect interview? 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. off original price! What is the difference between a logical and physical data model? Q #19) Employee health details are hidden from his employer by the health care provider. Q37). Ans: Data stored in form of rows and columns is called as table. There are a lot of opportunities from many reputed companies in the world. © Copyright SoftwareTestingHelp 2020 — 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? Another reason for using snowflake schema was it is less memory consumption. Question3: What is a logical data model and logical data modeling? Answer: Data Modelling is the diagrammatic representation showing how the entities are related to each other. For better understanding purpose, these data models are split up into subject areas. For example, a one-to-many recursive relationship occurs when an employee is the manager of other employeess. What are the types of normalization? This difference between OLAP and OLTP also gives you the way to choosing the design of schema. Below are the varies types of SCDs. are stored in a repository, which can be accessed by data modelers and the entire team. Mindmajix - The global online platform and corporate training company offers its services through the best Physical Data Modeling Interview Questions and Answers. We first create the conceptual model, then the logical model and finally move to the physical model. Different categories of health care plans and products. Mindmajix offers Advanced Data Modeling Interview Questions 2020 that helps you in cracking your interview & acquire dream career as Data Modeling Architect. It shows how the entities are linked to each other. 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. Answer: No, it will not throw any error in this case because a null value is unequal to another null value. If you're looking for Data Modeling Interview Questions for Experienced or Freshers, you are at right place. Which level of data hiding is this? It can be a column or a combination of columns. Data Analysis Interview Questions. By providing us with your details, We wont spam your inbox. Here, a vehicle is a super-type entity. For Example, a date dimension can be used for “Date of Claim”, “Billing date” or “Plan Term date”. What is self-recursive relationship? For Example, all bikes are two-wheelers and all cars are four-wheelers. If the referenced column in the child table is a not a part of the primary key and standalone column in the child table, relationship is drawn by dotted lines by connecting these two tables, which is called as non-identifying relationship. The star schema is quite simple, flexible and it is in de-normalized form. In simple words, you can say that a DataMart is a subset of a data warehouse. On the contrary, star schema has a high level of redundancy and thus it is difficult to maintain. Q42). Q40). Data Modeling Interview Questions for Freshers & Experienced Q1). Ans: When more than one column is a part of the primary key, it is called as composite primary key constraint. Snow Flake: Its almost like starschema but in this our dimension tables are in 3rd NF, so more dimensions tables. The facets database in my project was created with SQL server 2012. These are the dimensions where attribute values vary with time. Comprehensive, community-driven list of essential Data Modeling interview questions. Answer: Facts represent quantitative data. Unlike a primary key, it is not picked up from the existing application data fields. Q #3) Throw some light on your experience in Data Modelling with respect to projects you have worked on till date? You can see that the above table does not contain any measure. Q18). Data modeling interview questions are those designed for candidates to display introductory to expert level knowledge of data modeling principles and practices. Q #21) What particulars you would need to come up with a conceptual model in a health care domain project? The coupon code you entered is expired or invalid, but the course is still available! Whether you're a candidate or interviewer, these interview questions will help prepare you for your next Data Modeling interview ahead of time. all databases must be in third normal form? A logical data modeler  designs the data model to suit business requirements, creates and maintains the lookup data, compares the versions of data model, maintains change log, generate reports from data  model and whereas a physical data modeler has to know about the source and target databases properties.A physical data modeler should know the technical-know-how  to create data models from existing databases and to tune the data models with referential integrity, alternate keys, indexes and how to match indexes to SQL code. Ans: Constraint is a rule imposed on the data. ( 80% asked Data Modeling Interview Questions ) Answer : The first normal form is the normal form of database where data must not contain repeating groups.The database is in First normal form If, 1.It contains only automic values. Q # 14) What is a Surrogate key? On the contrary, OLAP is for analysis and reporting purposes & it is in de-normalized form. Still, we can pinpoint Top 20 financial modeling interview questions (with answers), which will help you leap from being a potential employee to a new one. Answer : Enterprise data model comprises of all entities required by an enterprise. DATA MODELING Interview Questions and Answers :- 1. Ans: You can take a report of the entire data model, or subject or part of the data model. What is a logical data model and logical data modeling? The approach by which data models are constructed for transactions is called as OLTP data modeling. For Example, the net amount due is a fact. Answer: Data marts are for the most part intended for a solitary branch of business. Ans: Usually, in a data model, parent tables and child tables are present. is a non-additive measure. This is a case where a derived, rather than a natural, primary key is appropriate. What is a physical data model and physical data modeling? Q17). Primary Key=Unique + Not Null. Machine Learning Interview Questions. All the dimension tables are connected to the fact table. The different types of constraints are primary key, unique, not null, foreign key, composite foreign key, check constraint etc. Top 50+ Database Interview Questions and Answers. Q41). Ans: Row also known as tuple or record is the horizontal alignment of the data. I did the Bar raiser round well too. In relational terms, every column in a table must be functionally dependent on the whole primary key of that table. And why do we use it? Every interview is different and the scope of a job is different too. Ans: Data sparsity is term used for how much data we have for a particular dimension/entity of the model.It affects aggregation depending on how deep the combination of members of the sparse dimension make up. Join our subscribers list to get the latest news, updates and special offers delivered directly in your inbox. A data model is a conceptual representation of business requirement (logical data model) or database objects (physical) required for a database and are very powerful in expressing and communicating the business requirements and database objects. If the combination is a lot and those combination do not have any factual data then creating space to store those aggregations will be a waste as a result, the database will become huge. In simpler words, it is a rational or consistent design technique used to build a data warehouse. This could be defined as a substitute for natural keys. Deep Learning Interview Questions. Answer: Generally, the fact table is in normalized form and the dimension table is in de-normalized form. Ans: Data Model and its relevant data like entity definition, attribute definition, columns, data types etc. Logical | Physical Data Modeling:Ans: When a data modeler works with the client, his title may be a logical data modeler or a physical data modeler or combination of both. In a data model, entities (tables) look like square boxes or rectangular boxes, which contain attributes and these entities, are connected by lines (relationship). To convert first-normal-form tables to second-normal-form tables, remove columns that are not dependent on the primary key. Q #2) Explain your understanding of different data models? Ans: Sequence is a database object to generate a unique number. Type of subscription (group or individual). The process of removing data redundancy is known as normalization. Q #12) What do you understand by data mart? Q26). What is data modeling? Question 7 : What is first normal form ? Ans: Denormalization is used when there are a lot of tables involved in retrieving data. What Is An Enterprise Data Model? List of Most Frequently Asked Data Modeling Interview Questions And Answers to Help You Prepare For The Upcoming Interview: Here I am going to share some Data Modeling interview questions and detailed answers based on my own experience during interview interactions in a few renowned IT MNCs. Q47). For Example, if the subscriber dimension is connected to two fact tables – billing and claim then the subscriber dimension would be treated as a conformed dimension. Interview Questions for Data Modeling.How prolonged do you plan to stay at company if offered the Data Modeling position?What was the most … Question5: What is the difference between a logical and physical data model? Answer: There are typically five types of dimensions. Ans: In general all organization data bases are normalized to 3nf in order to remove redundancy and efficient access. This helps to quickly retrieve the information from the database. Semi- additive measures are the ones on top of which some (but not all) aggregation functions can be applied. Q #6) Which schema is better – star or snowflake? 36 Data Modeling Questions and Answers: 1:: Give us a non-computer example of … What are the different types of constraints? Explain with example. What is non-identifying relationship? What is the difference between star flake and snow flake schema?