It is very common to see in a relational database that stored procedures are using many Tables, Views, Sequence Object, Stored Procedures, Functions, or many more to process the business logic. If you happen to work on a Stored Procedure performance issue which referenced many objects, you might end up asking yourself – “Is the […]
How to Perform Database Hack-Attach
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This blog demonstrates attaching a database on the SQL Server Instance which already has the same name database up and running. Scenario: Suppose, you got a hardware migration activity. The migration activity involves moving the databases from old hardware to new hardware. Let’s say the server got only one big database to be migrated. During […]
Finding Untrusted Foreign Keys and Constraints
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In the previous blog, we discussed the Foreign Keys Constraints and how the CHECK Constraints are useful to verify the data that goes into your tables. But, sometimes when you need to load a lot of data quickly, SQL Server allows you to temporarily disable any CHECK or FOREIGN KEY constraint in order to improve performance. […]
Find Missing Indexes For All SQL Server Databases
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DMV (Database Management View) and DMO (Database Management Objects) were added in 2005. There have been huge improvements in each new edition of SQL Server. It provides us a lot of useful information about SQL Server like – expensive queries, wait type, missing index…., and the list goes on and on… In this blog, I […]
SQL Server Logical Query Processing
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Recently, while reviewing one of the stored procedure performance, I suggested a couple of changes to a developer to improve the performance of the SP. One of the suggestions was to replace DISTINCT with GROUP BY. A few days later, he came back to me with a performance matrix to show that there was no […]
How to Check SQL Server View Utilization
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If you are working on SQL Server optimization delicately, you may get often queries that how to find if any index, table or view is being used in database or not. In recent past, we went live for one of the critical application. The developers decided to check through all the indexes utilization including View indexes […]
What is a Foreign Key & How many foreign keys can you have on a single table?
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Yesterday, I was attending a database design meeting. In the meeting, I was asked one of the questions – “How many foreign keys can you have on a single table?” Honestly, I had no clue about the limit. But, I must acknowledge that it was an excellent question to learn something new. Once the meeting […]
How SQL Compilation Can Prove the Server CPU
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It is relatively easy to spot CPU-bound system. But, the source of CPU pressure is not always easy to pinpoint. The CPU can be driven by many factors on the server such as; Memory pressure which is causing SQL Server to continually move data in and out of the memory. Disk latency Bad indexes Poorly […]
SQL Performance – Using Query Hint OPTION (FAST N)
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It is fun working with SQL/Application developer where you exchange a lot of technical thoughts to find the root of the issues. Recently, one of the developers optimized the OLTP system stored procedure by putting the query hint OPTION (FAST ‘N’). But, he was not sure enough about the drawback of the query hint. So, he […]
New Built-in Function CONCAT_WS() – SQL Server 2017
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In my previous post on new functions in SQL Server 2017, I discussed about the STRING_AGG function. Here, I am going to discuss about the function CONCAT_WS. This function concatenates a variable number of arguments with a delimiter specified in the first argument. Syntax for the function CONCAT_WS ( separator, argument1, argument1 [, argumentN]… ) […]