Apache Spark is a popular big data processing engine that is designed to handle large-scale data processing tasks. When it comes to writing data to JDBC, Spark provides a built-in JDBC connector that allows users to write data to various relational databases easily. We can write Spark dataframe to SQL Server, MySQL, Oracle, Postgres, etc. […]
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Query performance tuning – Introduction Query performance tuning is a process of improving system performance to make it faster and more scalable. It is a creative and iterative process which has a clear and well-defined objective. To achieve this goal, we have to follow certain defined steps. Why we need this Enterprise data changes frequently over
In this post we are going to find the total number of spaces in a given string. I have a string which contains spaces at multiple places and i just want to count them all. We can achieve this in various ways. Here, i am sharing some of these methods. Why i am doing this
Count of total spaces in a string in SQL Server – Various methods Read More »
Before having a discussion on “Indexed views in SQL Server”, let’s talk about simple view first. A view is a virtual table which contains a SELECT statement to be executed when this view is called. It does not store any physical data and processes the data at run time. This can be used as a table
Lets explore the topic “Index Join in sql server” starting with “what is index join?”. Index join is a technique which uses an index intersection with two or more indexes to fulfill a query completely. If a table has multiple small index instead of a large covering index, the optimizer can choose index intersection on these
In this topic we are going to compare clustered indexes with nonclustered indexes with their usage and performance and will also discuss some points regarding the topic “when to choose which one”. Clustered Vs NonClustered indexes is an old topic and you can get many article written so far. But in this post I will cover the definitions, structure of
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In this article, we are going to discuss the SQL Server’s query execution flow architecture. When a query gets submitted to SQL Server, it goes through multiple steps before final output. We will discuss all these steps of “Query Execution Flow” starting from query submission to getting output. As we all know that SQL Server has various components
In this article, i will introduce the internal join techniques, which sql server uses to perform various joins internally also known as Nested Loop, Merge and Hash Joins. These types are not directly exposed to us but we can use them as a query hint. These are also known as physical joins in SQL Server. So lets
