Top 50 MySQL Interview Questions and Answers


Book Description

This book contains basic to expert level MySQL interview questions that an interviewer asks. Each question is accompanied with an answer so that you can prepare for job interview in short time. We have compiled this list after attending dozens of technical interviews in top-notch companies like- Google, Facebook, Netflix, Amazon etc.Often, these questions and concepts are used in our daily programming work. But these are most helpful when an Interviewer is trying to test your deep knowledge of MySQL.The difficulty rating on these Questions varies from a Fresher level software programmer to a Senior software programmer. Once you go through them in the first pass, mark the questions that you could not answer by yourself. Then, in second pass go through only the difficult questions. After going through this book 2-3 times, you will be well prepared to face a technical interview on MySQL for an experienced programmer. Some of the questions are:How will you calculate the number of days between two dates in MySQL?What are the different types of Triggers in MySQL?What are the differences between Heap table and temporary table in MySQL?What is a Heap table in MySQL?What is the difference between BLOB and TEXT data type in MySQL?What will happen when AUTO_INVREMENT on an INTEGER column reaches MAX_VALUE in MySQL?What are the advantages of MySQL as compared with Oracle DB?What are the disadvantages of MySQL?What is the difference between CHAR and VARCHAR datatype in MySQL?What is the use of 'i_am_a_dummy flag' in MySQL?How can we get current date and time in MySQL?What is the difference between timestamp in Unix and MySQL?How will you limit a MySQL query to display only top 10 rows?What is automatic initialization and updating for TIMESTAMP in a MySQL table?How can we get the list of all the indexes on a table?What is SAVEPOINT in MySQL?17. What is the difference between ROLLBACK TO SAVEPOINT and RELEASE SAVEPOINT?How will you search for a String in MySQL column?How can we find the version of the MySQL server and the name of the current database by SELECT query?What is the use of IFNULL() operator in MySQL?How will you check if a table exists in MySQL?How will you see the structure of a table in MySQL?What are the objects that can be created by CREATE statement in MySQL?24. How will you see the current user logged into MySQL connection?How can you copy the structure of a table into another table without copying the data?What is the difference between Batch and Interactive modes of MySQL?How can we get a random number between 1 and 100 in MySQL?What is the difference between Primary key and Candidate key?What is a Federated table in MySQL?How will you get the comma separated values for a column in a MySQL Group query?How can we get the results from a table in a random order in MySQL?How can we prevent duplicate records in a MySQL table?How will you eliminate duplicate values from a query result in MySQL?How will you get the size of data in a MySQL table?What is the option in Amazon Web Services for MySQL?How can we manage multiple MySQL servers?How will you migrate your SQL Server database to MySQL?What is the difference between MySQL and Oracle?What is the order of privileges in MySQL?Is it ok to mention a table name in lower case while creation and in uppercase while retrieving data from MySQL DB?Why this query does not work in MySQL?What is mysqldump?What is the limitation of mysqldump?Can we run Javascript or Python code in MySQL?What are user-defined variables in MySQL?How will you optimize a SELECT query in MySQL?What are the different optimization techniques in MySQL?How can we optimize INSERT query in MySQL?How will you make MySQL system secure against attackers?How can you protect your MySQL server against Denial of Service attacks?




Interview Questions and Answers


Book Description




Learning MySQL


Book Description

This new book in the popular Learning series offers an easy-to-use resource for newcomers to the MySQL relational database. This tutorial explains in plain English how to set up MySQL and related software from the beginning, and how to do common tasks.




T-SQL Window Functions


Book Description

Use window functions to write simpler, better, more efficient T-SQL queries Most T-SQL developers recognize the value of window functions for data analysis calculations. But they can do far more, and recent optimizations make them even more powerful. In T-SQL Window Functions, renowned T-SQL expert Itzik Ben-Gan introduces breakthrough techniques for using them to handle many common T-SQL querying tasks with unprecedented elegance and power. Using extensive code examples, he guides you through window aggregate, ranking, distribution, offset, and ordered set functions. You’ll find a detailed section on optimization, plus an extensive collection of business solutions — including novel techniques available in no other book. Microsoft MVP Itzik Ben-Gan shows how to: • Use window functions to improve queries you previously built with predicates • Master essential SQL windowing concepts, and efficiently design window functions • Effectively utilize partitioning, ordering, and framing • Gain practical in-depth insight into window aggregate, ranking, offset, and statistical functions • Understand how the SQL standard supports ordered set functions, and find working solutions for functions not yet available in the language • Preview advanced Row Pattern Recognition (RPR) data analysis techniques • Optimize window functions in SQL Server and Azure SQL Database, making the most of indexing, parallelism, and more • Discover a full library of window function solutions for common business problems About This Book • For developers, DBAs, data analysts, data scientists, BI professionals, and power users familiar with T-SQL queries • Addresses any edition of the SQL Server 2019 database engine or later, as well as Azure SQL Database Get all code samples at: MicrosoftPressStore.com/TSQLWindowFunctions/downloads




Joe Celko's SQL Puzzles and Answers


Book Description

Joe Celko's SQL Puzzles and Answers, Second Edition, challenges you with his trickiest puzzles and then helps solve them with a variety of solutions and explanations. Author Joe Celko demonstrates the thought processes that are involved in attacking a problem from an SQL perspective to help advanced database programmers solve the puzzles you frequently face. These techniques not only help with the puzzle at hand, but also help develop the mindset needed to solve the many difficult SQL puzzles you face every day. This updated edition features many new puzzles; dozens of new solutions to puzzles; and new chapters on temporal query puzzles and common misconceptions about SQL and RDBMS that leads to problems. This book is recommended for database programmers with a good knowledge of SQL. - A great collection of tricky SQL puzzles with a variety of solutions and explanations - Uses the proven format of puzzles and solutions to provide a user-friendly, practical look into SQL programming problems - many of which will help users solve their own problems - New edition features: Many new puzzles added!, Dozens of new solutions to puzzles, and using features in SQL-99, Code is edited to conform to SQL STYLE rules, New chapter on temporal query puzzles, New chapter on common misconceptions about SQL and RDBMS that leads to problems




SQL Server Interview Questions and Answers


Book Description

As representatives from the IT community, all of us have had our own experiences of attending interviews - clearing or close to clearing and sometimes with tons of questions and doubts failing miserably. These stories are in the most pleasant or not so pleasant memories of our mind and we will assure you this book will kindle those memories for sure. We have taken tons of interviews and most of the interviews are not revolving around how deep technical and internals you know about the subject - but it revolves around how good you are with the basics.To clear an interview, one doesn't need to know inside-out of a subject, and subjects like "SQL Server" so vast that every single day we learn something new with this product, and even a complete lifetime will fly off if we keep doing this. Again, the various roles one can get into for products like SQL Server are from Database Developer, Database Modelers, Database Architect, Database Administrator and many more. Hence, this book is geared towards demystifying and a refresher for memories on the fundamentals which sometimes are the most important things to clear any type of interview for any role. Some of the concepts discussed are generic and are not tied to any specific version of SQL Server, but most of it the new features introduced with SQL Server have been included in this book.This book is not a shortcut or a sure to crack interview guide but this book gets you prepared in an organized manner. Let us also assure you this is neither a completely comprehensive guide but surely is a great starter nevertheless. Use this to guide you and be mentally prepared for the big day. When faced with this big day, we get overwhelmed and confused about where to start our preparation. And this book is just that secret recipe in your arsenal to get geared up. Sometimes these basics will help you narrow to a solution quickly when given a scenario.Now this book's flow is "Question & Answer" mode from start till the end to help you grasp the concepts faster and to the point. Once you get an understanding of concepts, then if we are twisted with the concept in a scenario it becomes easy to solve them. Most companies have a typical way to do interviews which are based on the scenario as per their environment and these are just combinations of the concepts to fit their need and SLA.Though each of these chapters is bucketed for convenience we highly recommend reading each of the sections nevertheless irrespective of the roles you might be doing as each of the sections have some interesting trivia's working with SQL Server. In the industry, the role of accidental DBA's especially with SQL Server is so common. Hence if you have performed the role of DBA for a short stink and want to brush-up your fundamentals then the respective sections will be a great skim.







Java/J2EE Job Interview Companion


Book Description

400+ Java/J2EE Interview questions with clear and concise answers for: job seekers (junior/senior developers, architects, team/technical leads), promotion seekers, pro-active learners and interviewers. Lulu top 100 best seller. Increase your earning potential by learning, applying and succeeding. Learn the fundamentals relating to Java/J2EE in an easy to understand questions and answers approach. Covers 400+ popular interview Q&A with lots of diagrams, examples, code snippets, cross referencing and comparisons. This is not only an interview guide but also a quick reference guide, a refresher material and a roadmap covering a wide range of Java/J2EE related topics. More Java J2EE interview questions and answers & resume resources at http: //www.lulu.com/java-succes




SQL Practice Problems


Book Description

Real-world practice problems to bring your SQL skills to the next level It's easy to find basic SQL syntax and keyword information online. What's hard to find is challenging, well-designed, real-world problems--the type of problems that come up all the time when you're dealing with data. Learning how to solve these problems will give you the skill and confidence to step up in your career. With SQL Practice Problems, you can get that level of experience by solving sets of targeted problems. These aren't just problems designed to give an example of specific syntax, or keyword. These are the common problems you run into all the time when you deal with data. You will get real world practice, with real world data. I'll teach you how to "think" in SQL, how to analyze data problems, figure out the fundamentals, and work towards a solution that you can be proud of. It contains challenging problems, that hone your ability to write high quality SQL code. What do you get when you buy SQL Practice Problems? You get instructions on how set up MS SQL Server Express Edition 2016 and SQL Server Management Studio 2016, both free downloads. Almost all the SQL presented here works for previous versions of MS SQLServer, and any exceptions are highlighted. You'll also get a customized sample database, with video walk-through instructions on how to set it up on your computer. And of course, you get the actual practice problems - 57 problems that you work through step-by-step. There are targeted hints if you need them that help guide you through the question. For the more complex questions there are multiple levels of hints. Each answer comes with a short, targeted discussion section with alternative answers and tips on usage and good programming practice. What kind of problems are there in SQL Practice Problems? SQL Practice Problems has data analysis and reporting oriented challenges that are designed to step you through introductory, intermediate and advanced SQL Select statements, with a learn-by-doing technique. Most textbooks and courses have some practice problems. But most often, they're used just to illustrate a particular piece of syntax, with no filtering on what's most useful. What you'll get with SQL Practice Problems is the problems that illustrate some the most common challenges you'll run into with data, and the best, most useful techniques to solve them. These practice problems involve only Select statements, used for data analysis and reporting, and not statements to modify data (insert, delete, update), or to create stored procedures. About the author: Hi, my name is Sylvia Moestl Vasilik. I've been a database programmer and engineer for more than 15 years, working at top organizations like Expedia, Microsoft, T-Mobile, and the Gates Foundation. In 2015, I was teaching a SQL Server Certificate course at the University of Washington Continuing Education. It was a 10 week course, and my students paid more than $1000 for it. My students learned the basics of SQL, most of the keywords, and worked through practice problems every week of the course. But because of the emphasis on getting a broad overview of all features of SQL, we didn't spend enough time on the types of SQL that's used 95% of the time--intermediate and advanced Select statements. After the course was over, some of my students emailed me to ask where they could get more practice. That's when I was inspired to start work on this book.




Sql Server - Interview Questions


Book Description