To answer the question: would would include, omit or revise the default correlation name to make the code to aid the human coder -- easier to read and understand means it will be easier to maintain -- but tastes vary (when the same table is involved in a query more than once then you...
There are two parts of a subquery. The two parts involve the outer query and the inner query. The inner query is basically called as a subquery, and the outer query is known as the main query in the Database. The implementation of subqueries is always done first, and the outcome of th...
Now that we have understood how to see a query plan let try to understand the first basic operator i.e. table scan. In order to understand the same we have created a simple companies table with company code and description. Do not create any primary key or indexes. Now write a simple ...
can help you answer questions. When you use SQL, you must use the correct syntax. Syntax is the set of rules by which the elements of a language are correctly combined. SQL syntax is based on English syntax, and uses many of the same elements as Visual Basic for Applications ...
One of the most common questions during this process is about how to check query performance in SQL Server, a common SQL-based database. If you’re wonderinghow to check database performance in SQL Server, you would do well to start with investigating your queries and improving how they per...
SQL: Frequently Asked Questions What is SQL used for? SQL is used for managing and manipulating data in relational database management systems (RDBMS). It allows users to query, update, and delete data from databases. What are the main components of an SQL statement?
BACKUP (Transact-SQL) Provides answers to basic questions that are related to backups. Provides examples of different kinds of backup and restore operations. Backup Devices (SQL Server) Provides a great reference for understanding various backup devices, backing up to a network share, Azure blob ...
A subquery answers multiple-part questions. For example, to determine who works in Taylor's department, you can first use a subquery to determine the department in which Taylor works. You can then answer the original question with the parent SELECT statement. A subquery in the FROM clause of...
Frequently asked questions about PolyBase. Compare PolyBase and linked servers and compare PolyBase in Big Data Clusters and PolyBase in stand-alone instances. Find out what's new in PolyBase.
Of course, reading just that is not enough, you should have tried those things to better answer the questions. Also check out the section titled "Backward Compatibility" in books online which talks about the changes that have taken place in the new version. 1. What are constraints? Explain ...