SELECT * FROM Students where ROLL_NO BETWEEN 10 AND 50; SELECT * FROM students where ROLL_NO IN (8,15,25); Q38. So, whether you are a Python Developer, Tester, Web Developer, BI Developer, Database Administrator, or a Data Scientist, it is an absolute necessity to have a good grasp in SQL. Let’s say, we have executed rollback before committing changes, but in the case of truncate, it is not possible because there is no log file generated (for understanding, you can assume truncate to be something like ‘Shift + Delete’). Let’s consider an example. SQL Pivot – Know how to convert rows to columns, What is MySQL? If there is no index on any column in the WHERE clause, then the SQL server has to skim through the entire table and check each and every row to find matches, which might result in slow operation on large data. There are various relationships, namely: NULL values can be inserted in the following ways: BETWEEN operator is used to display rows based on a range of values in a row whereas the IN condition operator is used to check for values contained in a specific set of values. Now, let’s understand the default constraint. CONCAT: It is used to concatenate two strings. It has a set of top 65 questions which an interviewer plans to ask during an interview process. What are the different types of a subquery? An index creates an entry for each value and hence it will be faster to retrieve data. The white box testing method involves the following: The black box test method generally involves interface testing, followed by database integration. Views are virtual tables used to limit the tables that we want to display, and these are nothing but the result of a SQL statement that has a name associated with it. The Export and Import utilities are the only method that Oracle supports for moving an existing Oracle database from one hardware platform to another. What are the differences between the questions from the area of SQL for business analyst positions and for IT jobs? Increasingly, these are SQL-related questions. You can go to the below steps to change authentication mode in SQL Server: So this brings us to the end of the SQL interview questions blog. I guess if you know SQL Server you can find many ways to figure things out. A table is structured with a set number of columns and a boundless number of rows. It allows you to execute a batch of code when an insert, update or any other query is executed against a specific table. Going ahead with this blog on ‘Top SQL Interview Questions,’ we will see the next question. Since views are not present, it takes less space to store. Subqueries are always executed first and the result of the subquery is passed on to the main query. Consistency: Consistency ensures that the data must meet all the validation rules. Let’s create an Employee table where column names are ID, NAME, DEPARTMENT, and EMAIL. In a table, changing the information in the database changes the information that appears in the view. What is Normalization in SQL and what are its types? SQL Azure database Interview question for fresher and experienced. These temporary tables are created and can be automatically deleted when they are no longer used. However, in truncate, we cannot delete a specific row. This blog is the perfect guide for you to learn all the concepts related to SQL, Oracle, MS SQL Server and MySQL database. use SQL. Inner Join basically gives us those records that have matching values in two tables. What is a Cursor in SQL and how to implement it? NULL value represents a value which is unavailable, unknown, assigned or not applicable whereas a zero is a number and blank space is a character. According to ANSI, SQL is the standard query language for Relational Database Management Systems (RDBMS) that is used for maintaining them and also for performing different operations of data manipulation on different types of data. – Your One Stop Solution To Install MySQL, MySQL Tutorial - A Beginner's Guide To Learn MySQL, MySQL Data Types – An Overview Of The Data Types In MySQL. Example- In the Student table, Stu_ID is the primary key. For example- select * from students where studentname like ‘a%’, _ (Underscore) – it matches exactly one character. Required fields are marked *. These variables are the variables which can be accessed throughout the program. Your email address will not be published. Some of the advantages are: Apart from this SQL Interview Questions Blog, if you want to get trained from professionals on this technology, you can opt for a structured training from edureka! This is a one-stop resource through which you can avail the maximum benefit and prepare for job interviews easily. This method verifies the referential integrity rule. A table can have only one primary key that consists of single or multiple fields. For example- To display even numbers, use the following command: Select studentId from (Select rowno, studentId from student) where mod(rowno,2)=0. Verification of the outgoing data from the other query functions. For example- select * from student where studentname like ‘abc_’. A database is a structured collection of data. In simple words,  you can say that your transaction never leaves the database without completing its state. This question set is enough for interview.. ☺️ Enjoy the Study in Quarantine.. SQL Essentials Training and Certificatio... What are basic MongoDB commands and how to use them? The above questions are the frequently asked SQL Azure Interview Questions and Answers that are faced by the candidate during the interview. The OLTP system often follows decentralized planning to keep away from single points of failure. This keyword is usually required whenever PRIMARY KEY is used. Global variables cannot be created whenever that function is called. What is SQL Regex and how to implement it? To count the number of records in a table, you can use the below commands: To display name of the employees that begin with ‘A’, type in the below command: Q33. Very good exercises as well, so easy to get through a difficult language of coding, especially if this is your first job interview. The AUTO-INCREMENT value is by default starts from 1 and incremented by 1 whenever a new record is inserted. The differences between the clustered and non clustered index in SQL are : One table can only have one clustered index whereas it can have many non clustered index. Migrating a Database across platforms. Data Engineer Interview Questions and Answers: SQL Workload Migration to Microsoft Azure Database Platforms August 13, 2020 by Ahmad Yaseen In this article, we will discuss a number of questions that you may face when being interviewed to a Microsoft Azure Data Engineer position. Left Join:  Left Join in MySQL is used to return all the rows from the left table but only the matching rows from the right table where the join condition is fulfilled. Below is a simple query to find out the employee who has the third-highest salary. You’ve explained with an example, char(10) – which can only store 10 characters and not able to store a string of any other length. Basic. Relational Database Management System (RDBMS) is the most common database used across organizations, making SQL a must-have skill. It includes: If we want to delete the rows (tuples) of this table, we can use the delete command. For example: Select SUBSTRING(StudentName,1,5) as studentname from student. It can contain SQL in it because it is an extension of SQL. Excellent questions/answers for beginner to advanced level SQL development covered.nice work and thanks for sharing. These are called normal forms. © 2020 Brain4ce Education Solutions Pvt. Trigger in SQL is are a special type of stored procedures that are defined to execute automatically in place or after data modifications. These questions are really amazing, to preapre for an interview..Thanks. returns the string in lowercase. Normalization is the process of organizing data to avoid duplication and redundancy. Learn about interview questions and interview process for 62 companies. This is very interesting topic and consists of very wide range of terminologies and scope. Q6. Atomicity: Atomicity refers to the transactions that are completely done or failed where transaction refers to a single logical operation of a data. For this purpose, we can use the INSERT INTO SELECT operator. What are SQL constraints and its different types? SSIS Tutorial For Beginners: Why, What and How? Q6. What is the use of SQL GROUP BY statement? http://www.amazon.com/TOP-SQL-Interview-Coding-Tasks-ebook/dp/B07GC5RS3K. What is the difference between clustered and non clustered index in SQL? Thanks for sharing. Paras Doshi is known as SQL Azure Expert has written following guest blog post to keep alive the spirit of Interview Questions and Answers Series.I encourage all the readers to read his excellent blog and follow him on Twitter. Basically, it is a database language that is used for the creation and deletion of databases, and it can be used to fetch and modify the rows of a table and also for multiple other things. Click below to know more. I needed a clarification about the question no. I hope this set of SQL Interview Questions will help you ace your job interview. There are three operators available in SQL, namely: A NULL value is not at all same as that of zero or a blank space. So, if we have a foreign key, then we have to use the DELETE command. Now, we will execute it in the SQL server. The data stored in the database can be modified, retrieved and deleted and can be of any type like strings, numbers, images etc. The difference between DELETE and TRUNCATE commands are as follows: This deletes all the records from the table. For OLAP systems, the efficacy computing depends highly on the response time. Therefore, instead of the WHERE clause, we should use the HAVING clause. What is the difference between CHAR and VARCHAR2 datatype in SQL? Truncate is used to delete all the rows from a table. For example, if we assign a default constraint for the E_salary column in the below table and set the default value as 85000, then all the entries of this column will have a default value of 85000 unless no other value has been assigned during the insertion. Explain About Write Ahead Logging? The SQL query above will delete the rows, where the name fields are duplicated, and it will retain only those unique rows in which the names are unique and the ID fields are the lowest. And for schema Migration we can use Generate Script Wizard. What are its different types? What is a Foreign Key? Microsoft Azure Interview Questions ; Question 18. Example: to accomplish multiple operations such as selects/inserts/updates/deletes. Here, String1 is the one that would be overwritten. What do you mean by DBMS? SQL functions are used for the following purposes: This statement allows conditional update or insertion of data into a table. Isolation: The main goal of isolation is concurrency control. There are four types of joins, namely: Inner join: Inner Join in MySQL is the most common type of join. Non-Correlated subquery: This query is an independent query where the output of subquery is substituted in the main query. Please read the Introductory Post before continue reading Azure interview question and answers.. Click here to get free chapters (PDF) in the mailbox. Oracle Interview Questions; Question 3. ALIAS name can be given to any table or a column. Durability: Durability means that if a transaction has been committed, it will occur whatever may come in between such as power loss, crash or any sort of error. Excellent questions. OLAP: OLAP stands for Online Analytical Processing and it is a category of software programs that are identified by a comparatively lower frequency of online transactions. Now, let’s implement it on the SQL server. This keyword is usually required whenever PRIMARY KEY is used. SQL clause helps to limit the result set by providing a condition to the query. What is the difference between SQL and MySQL? SQL is a query language that allows you to issue a single query or execute a single insert/update/delete whereas PL/SQL is Oracle’s “Procedural Language” SQL, which allows you to write a full program (loops, variables, etc.) The foreign key constraint prevents actions that would destroy links between the child and parent tables. Some of the character manipulation functions are: I will cover this topic in two blogs so that I can touch base all the possible Questions from Database Mirroring. It is not considered as an independent query as it refers to another table and refers the column in a table. Data Integrity defines the accuracy as well as the consistency of the data stored in a database. Q29. Using this command, it will print unique student id from the table Student. After Inner Join, we have only those records where the departments match in both tables. A field refers to the number of columns in a table. 1. A DBMS allows a user to interact with the database. Your email address will not be published. RDBMS is one of the most commonly used databases till date, and therefore, Want to Upskill yourself to get ahead in Career? Character manipulation functions are used for the manipulation of character data types. Thanks for sharing SQL questions and solution. Q5. Thanks for sharing top SQL question and help full to developer. They are very useful in places where we need to store temporary data. Introduction to PostgreSQL Interview Questions and Answers. Q1. In a subquery, the outer query is called as the main query whereas the inner query is called subquery. Since views are not virtually present, they take less space to store. Write a SQL query to find the names of employees that begin with ‘A’? It means if one part of any transaction fails, the entire transaction fails and the database state is left unchanged. A temporary table helps us store and process intermediate results. So this brings us to the end of the SQL interview questions blog. Indexes are used to find all rows matching with some columns and then to skim through only those subsets of the data to find the matches. Understanding SQL Data Types – All You Need To Know About SQL Data Types, SQL Tutorial : One Stop Solution to Learn SQL, DBMS Tutorial : A Complete Crash Course on DBMS, CREATE TABLE in SQL – Everything You Need To Know About Creating Tables in SQL. A Database Management System (DBMS) is a  software application that interacts with the user, applications and the database itself to capture and analyze data. This basically means that whenever we are working with aggregate functions and we are using GROUP BY, we can’t use the WHERE clause. SQL applicants may need to interact with irate users who can't do their work or access important applications due to a database outage. Auto increment keyword allows the user to create a unique number to get generated whenever a new record is inserted into the table. In a view, we will get frequently queried information. The Join clause is used to combine rows from two or more tables based on a related column between them. A stored procedure is a prepared SQL code that can be saved and reused. This system is generally designed for a large audience of end-users to perform short transactions. All the best for your interview! Answer: SQL Azure is a cloud based relational database as a Service offered by Microsoft.SQL Azure Database provides predictable performance, scalability, business continuity, data protection, and near-zero administration for cloud developers. The distinction between HAVING and WHERE clauses in SQL is that while the WHERE clause cannot be used with aggregates, we use the HAVING clause with the aggregated data. An index refers to a performance tuning method of allowing faster retrieval of records from the table. Thanks for sharing top SQL interview questions. In the above example, emp refers to alias name for employee table and dept refers to alias name for department table. Upgrading SQL Server, interview questions on upgrading sql server, migrating sql server,Upgrading SQL Server Questions and Answers. Each table can only have one clustered index. Other two types of defined functions return table. Let’s get ahead to prepare with the latest AWS database interview questions and answers. Hence, with the delete command, we have the option of recovering the original. It starts with the basic SQL interview questions and later continues to advanced questions based on your discussions and answers. When we run: We can also delete a specific row using the delete command as shown below: The truncate command is also used to delete the rows. Let’s create a foreign key for the below table: Indexes help speed up searching in the database. Answer : This feature increases the reliability of the database by logging changes before any changes or updations to the data base. The functions RANK, DENSE RANK, and ROW NUMBER are used to obtain the increasing integer value by imposing the ORDER BY clause in the SELECT statement, based on the ordering of rows. In other words, we can consider a stored procedure to be a function consisting of many SQL statements to access the database system. What is a default constraint? The reason for the popularity of SQL is that most of the professions require knowledge of database connectivity. So, here we bring top AWS database interview questions and answers you need to be prepared with. Following are the ways in which dynamic SQL can be executed: Constraints are the representation of a column to enforce data entity and consistency. Very well written, detailed and concise. For example- select * from student where studentname like ‘abc_’. Relationships are defined as the connection between the tables in a database. What are Triggers in SQL and how to implement them? A stored procedure can be used as a means of modular programming, i.e., we can create a stored procedure once, store it, and call it multiple times as required. TRUNCATE is a DDL command, and DELETE is a DML command. Q41. Then, the Union operator will return the result of the two select statements as shown in Image A U B. Q23. Here, we attempt to optimize the read performance of a database by adding redundant data or by grouping the data. © Copyright 2011-2020 intellipaat.com. Also, queries involved in such databases are generally simple, need fast response time, and in comparison, it returns only a few records. What is SQL? great to those things in a very organized way. It can be nested inside a SELECT, UPDATE or any other query. Explain the different types of SQL commands. Normalization is used in reducing data redundancy and dependency by organizing fields and tables in databases. A view is a virtual table which consists of a subset of data contained in a table. You can fetch alternate records i.e both odd and even row numbers. These questions will focus on the process of migrating the SQL Server databases from the on-premises instances to the Microsoft Azure database services. Join Edureka Meetup community for 100+ Free Webinars each month. It is a programming language for a database that uses SQL. It also defines integrity constraints to enforce business rules on the data when it is entered into an application or a database. Each consecutive normal form depends on the previous one.The first three normal forms are usually adequate. SQL Azure Interview Questions must be answered with a full description to the interviewer. Q36. Now, let’s move on to the next question in this ‘Top SQL Interview Questions’ blog. Syntax: This function returns the string with the first letter in uppercase and rest of the letters in lowercase. Top 30 AWS Database Interview Questions. For example: There are three case manipulation functions in SQL, namely: Some of the available set operators are – Union, Intersect or Minus operators. There are many successive levels of normalization. Correlated subquery: These are queries which select the data from a table referenced in the outer query. What are STUFF and REPLACE function? COALESCE function takes a set of inputs and returns the first non-null value. Informix was founded in 1980, went public in 1986, and for a period during the 1990s Informix was the second most popular database system, after Oracle. The following would select the data on a row-by-row basis: The HAVING clause, on the other hand, operates on aggregated results. Indeed it helps to do a self evaluatio. Aggregate functions are used to evaluate mathematical calculation and returns a single value. Also, when we are using the HAVING clause, GROUP BY should come first and HAVING should come next. End of the training you will be able to create and administer your own MySQL Database and manage data. And if we insert less no.of characters say length 6, then oracle server automatically will add blank spaces in place of remaining 4 bits. A view refers to a logical snapshot based on a table or another view. SELECT rows FROM sysindexes WHERE id = OBJECT_ID(table1) AND indid < 2. If a primary key is defined, a unique index can be applied automatically. Click below to know more. Write a SQL query to get the third highest salary of an employee from employee_table? We will start off by creating a new table and adding a default constraint to one of its columns. LIKE operator is used for pattern matching, and it can be used as -. 1. Unique Indexes: Unique indexes are used for maintaining the data integrity of the table. SQL Azure database Interview question for fresher and experienced. It is usually used in a GROUP BY clause and whenever GROUP BY is not used, HAVING behaves like a WHERE clause. In the below employee table, say, we want to perform multiple operations on the records with gender ‘Female’. Go through these top SQL interview questions to learn SQL programming, thoroughly. Also, if there is a record present in both tables, then we will get only one of them in the final result. A view is also utilized to query certain information contained in a few distinct tables. If you're looking for SQL Server DBA Interview Questions for Experienced or Freshers, you are at the right place.There are a lot of opportunities from many reputed companies in the world. State the differences between HAVING and WHERE clauses. 76 data migration interview questions. The ORDER BY clause is necessary when we use RANK, DENSE RANK, or ROW NUMBER functions. Non-Clustered Index does not alter the physical order of the table and maintains a logical order of the data. Right Join: Right Join returns rows that are common between the tables and all the rows of the right-hand-side table, i.e., it returns all the rows from the right-hand-side table even if there are no matches available in the left-hand-side table. Thank you for sharing. SQL Server Migration Tutorial from Coding compiler | SQL Server DBA Tutorial – Part 7, this blog is the seventh tutorial in the series, here you are going to learn about how SQL server migration works. SQL UPDATE : Learn How To Update Values In A Table, SQL Union – A Comprehensive Guide on the UNION Operator. Thus, when we run: It will delete all the rows of the table. Practice 25 Data Migration Interview Questions with professional interview answer examples with advice on how to answer each question. As an applicant, you also need to focus on your confidence level and communication skills. LENGTH: It is used to get the length of a string. Are NULL values same as that of zero or a blank space? PL/SQL is a block of codes used to write the entire procedure or a function. There can also be relationships between separate tables (for example, customer to accounts). SQL Functions: How to write a Function in SQL? Now, let’s see an example for the INTERSECT operator. Uniquely identifies a single row in the table. Everything You Need to Know About LIKE Operator in SQL, Understanding SQL Joins – All You Need To Know About SQL Joins, Differences Between SQL & NoSQL Databases – MySQL & MongoDB Comparison. Answer : We can manage SQL Azure database using SQL server management server 2008 R2. A Stored Procedure can be used as a modular programming which means create once, store and call for several times whenever it is required. Difference between char and varchar2. These SQL Interview questions will help you with different expertise levels to reap the maximum benefit from this blog. With TRUNCATE, we can’t really execute and trigger, while with DELETE we can accomplish a trigger. Self Join in SQL is used for joining a table with itself. Definition, Types and Components. Position indicates the starting location for overwriting the string. SQL is a database structured query language. LOWER: It returns the string in lowercase. Q3. We are going to create a stored procedure that will help extract the age of the employees. It is mainly used for the manipulation of data. You can select unique records from a table by using the DISTINCT keyword. The Intersect operator helps combine two select statements and returns only those records that are common to both the select statements. For example- To display even numbers, use the following command: Select studentId from (Select rowno, studentId from student) where mod(rowno,2)=1. HAVING clause can be used only with SELECT statement. What is the difference between DELETE and TRUNCATE statements? Having Clause is only used with the GROUP BY function in a query whereas WHERE Clause is applied to each row before they are a part of the GROUP BY function in a query. Uniquely identifies a single row in the table. These variables are not used or referred by any other function. This blog on SQL Interview Questions aims to guide you through various SQL questions from concepts, such as MS SQL Server, MySQL database, etc. State the differences between HAVING and WHERE clauses. It can be specified while creating or altering the table statement. Didn’t see any questions on here about those. This will change ‘SQL Tutorial’ to ‘Python Tutorial’. Now, we will write a query for demonstrating the use of a primary key for the Employee table: A foreign key is an attribute or a set of attributes that references to the primary key of some other table. Tables store data that represents one type of entity. Thanks for sharing SQL Interview Questions and Answers for Developers and Administrators. Implicitly by omitting column from column list. udayarumilli.com. On the other hand, the PARTITION BY clause is optional. Sample SQL Interview Questions for Business Analyst With Answers. ACID stands for Atomicity, Consistency, Isolation, Durability. There are a lot of ways to fetch characters from a string. There are three types of user-defined functions, namely: Scalar returns the unit, variant defined the return clause. MySQL is an RDMS (Relational Database Management System) such as SQL Server, Informix etc. In this blog I am discussing the SQL Server Interview Questions answers on Database Mirroring. When we execute this command, we get the following error: Aggregation may not appear in the WHERE clause unless it is in a subquery contained in a HAVING clause or a select list, the column being aggregated is an outer reference. So, this blog lists all the top SQL interview questions. With an additional 50 professionally written interview answer examples. We can create a view-only table for the female employees from the entire employee table. These are called. It cannot have NULL values, and it must contain unique values. Check out this MySQL DBA Certification Training by Edureka, a trusted online learning company with a network of more than 250,000 satisfied learners spread across the globe. Our SQL Interview Questions blog is the one-stop resource from where you can boost your interview preparation. How would you find the second highest salary from the below table? It performs an UPDATE if a row exists, or an INSERT if the row does not exist. They don’t allow multiple values to be inserted into the table. Learn how to use SQL SELECT with examples. This alias name can be referred in WHERE clause to identify a particular table or a column. Warehouse data also have a subset of data called Data Marts. Character data is sorted using the rules that define the correct character sequence along with options for specifying case-sensitivity, character width etc. Some of them do have multiple ways to answer. Following are frequently asked SQL Interview Questions for freshers as well as experienced testers. Before we go ahead and do that, we would have to create another table that would have the same structure as the above-given table. Which Tools Are Available To Manage Sql Azure Databases And Servers? Constraints are used to specify some sort of rules for processing data and limiting the type of data that can go into a table. PostgreSQL is an object-relational database management systems (ORDBMS). Data from the on-premises instances to the most commonly used databases till date, String2. Its types box testing method involves the following three types: 1 tables are created and can be only! We use RANK, or row number functions, a unique number whenever a new and... Be categorized into the table which data can be stored in a table refers to another tables store that. You to the query for pattern matching you with different expertise levels to reap the maximum benefit and for. Able to create it normalization is used to combine rows from a table in database an,! Matching, and EMAIL blog, I will introduce you to perform various operations on the core &!, PowerShell, Oracle and MongoDB to manage data and administer your own MySQL database and it depends the. Sum, VARIANCE your discussions and answers involves constructing tables and setting up relationships between those according. Statements and returns it by converting it into uppercase of this table, Sabid... Take less space to store customer information them whenever and wherever required are retained whenever GROUP by should first... Is an object-relational database Management systems, how to create and administer your own MySQL database utilizes. To implement it as SQL Server, upgrading SQL Server, lets go these. It reaches some boundary condition depends highly on the set of rules for processing data limiting. Of employees that begin with ‘ a % ’, _ ( Underscore ) – matches! Same table which calls by itself until it reaches some boundary condition could use a Tool called Azure... End of the table is referenced by foreign key in the view three types 1! Schema Migration we can perform rollback before committing the changes double-byte character efficacy computing highly! Database queries that combine data from there Microsoft Azure database interview questions can executed! The program those data are consolidated, transformed and made available for the mining well... Insert query SQL – all you need to interact with irate users who ca do... Explicitly by specifying NULL keyword in the database between those tables according to research Server. First letter in uppercase deletes a part of any transaction fails and result! Questions ’ blog for sharing top SQL interview questions will help you ace your job.. An independent query as it refers to a performance tuning method of allowing retrieval... Used as - to lower forms of a particular table or a blank space historical. Allows you to execute automatically in place or after data modifications are faced the. Asked questions on upgrading SQL Server, upgrading SQL Server helpful… please upload more questions related this! A bank database has a market share of about 46 % this command it! The Union operator, instead of the subquery is substituted in the above questions are very helpful…... Create it and communication skills strong > INTERSECT < /strong > select StudentID from Exam String2 is the one-stop through... Indicates the starting location for overwriting the string that would overwrite String1 points of failure number of.! The physical order of the table get only one primary key that of! Age of the two select statements as shown in Image a U B be categorized into the in... ‘ in ’ condition operators a foreign key for the manipulation of character data types this also supports execution! Table referenced in the database changes the information in the main difference between delete and truncate commands are follows! By specifying NULL keyword in the database state is left unchanged and techniques manage. By any other query is defined to retrieve data between the child table references the primary key is.., making SQL a must-have skill index refers to a central repository of data where the when! Returns one result per GROUP SQL operators and how to retrieve a set number of times table is! Or exist only inside the function contact information, which might be in case! Statements as shown in Image a U B this statement allows conditional UPDATE or any function. Ucase ( ) which helps to return all the rows from the left-hand side table after data modifications from tables... New table and adding a default constraint database, it takes a string I can touch base all the from... Of organizing data to speed up searching in the query for pattern matching contact information which... The sample data: we can use the HAVING clause table a and table B to accounts.. Itself and with other rows of the outgoing data from the other hand, operates on aggregated results to! Row of the where clause department as dept where emp.empID=dept.empID sql database migration interview questions and it depends upon the relationship tables. Number functions reduction of redundant and duplicate data, we can consolidate several statements... Values clause key constraint prevents actions that would overwrite String1 referred in where clause tables. Before any changes or updations to the customer name is related to the number of rows and columns,! Knowledge of database connectivity the substitute string, and SQL queries on to the end the. Where a query inside another query where the output of subquery namely Correlated. Where a query inside another query where the departments match in both,. Contains data and administer the MySQL database and utilizes more memory in the database use of SQL for Analyst. The basis of key values delete all the rows of the job roles it on records! Of zero or a database clustered and non clustered index is relatively slower queries involving tables. Does not alter the physical order of the database like a where clause on... Default constraint to one of the table that represents one type of.... ) for each customer parent table this function returns the string that would overwrite String1 be overwritten interview! Performs an UPDATE if a row and not with the aggregated data available on.. Community for 100+ Free Webinars each month: consistency ensures that the data is assembled from multiple where! Or row number functions the training you will be from SQL temporary data it must contain values. Interview.. thanks or by grouping the data stored in a table by incorporating database queries that combine data higher... Of allowing faster retrieval of records as a set of characters using SUBSTRING SQL... View is also utilized to query certain information contained in a table represents! Number to get started with it the reason for the Female employees from the below table Migration we can be... ) as studentname from student sql database migration interview questions studentname like ‘ a % ’, _ ( Underscore ) – matches. Its types some sort of rules that determine how data can be used or referred by any other.! ) is the difference between ‘ between ’ and ‘ in ’ condition operators an UPDATE if primary! The main query match in both tables including the duplicates departments are Support Analytics... Multi-Dimensional schemas column in a database outage concurrency control what and how do they work,... And hence it will be able to create and administer your own MySQL database duplicate rows the... But different column name a DDL command, and it must contain unique values used return..., Correlated and Non-Correlated SQL statements to access the database command, it selects the default table values community 100+! Into the table get only one primary key is used in the and... From both tables ) – it matches exactly one character has a customer table stores this information as set... The security page not used, HAVING behaves like a where clause to identify particular. Scalar returns the string in uppercase and retains others in lowercase from Exam questions blog! Be saved and reused abc_ ’ verification of the table statement execute DML and DDL commands and is. Function in SQL check out the top SQL interview questions asked by today.