[Note from Pinal]: This is a 98th episode of Notes from the Field series. Maintenance of the database is a very critical activity and I have always seen DBA taking it very seriously. There is a only one problem – there is no single solution or guidance for how to maintain the database. Everybody has their own opinion and way to do different tasks. System maintenance is very straight forward task but I have seen quite often experts even getting confused with the same. Many only focus on index maintenance, statistics maintenance and a few other tasks are common, but understanding the real philosophy of this task is something beyond indexes. When I asked my good friend Stuart about system maintenance, he came up with very interesting guidelines for system maintenance.
SQL SERVER – What Does WHERE 1=1 Mean in the Code?
One of the blog followers asked this question “The code written by my colleague has WHERE 1=1. What does it mean?” Well. You have seen people using it when they dynamically construct WHERE condition based on the input values. Let us create this dataset CREATE TABLE #t (emp_name VARCHAR(100), experience…
Read MoreSQL SERVER – What is Windows Internal Database Edition?
The more you read the more you learn. But some of the best learnings need not come from known sources. These can be accidental too. These learnings in my opinion involves tons of exploration which you would have never done before. This blog post today is something on the similar…
Read MoreSQL SERVER – Fix: SQL Server CPU Schedulers Offline
Performance troubleshooting are some of the most common things I get to see as part this blog. A number of you keep sending me interesting mails that keep me up-to-date on my learnings. Yes, it is tough to know everything, but at the same time, it is almost impossible to…
Read MoreSQL SERVER – Basic architecture of Transaction Logs
Readers bump into this blog because it tries to simplify some of the most complex topics into a digestible format. I am a strong believer of this and try to bring some of these topics from time-to-time. Even I find some of these topics confusing, if I can understand them…
Read MoreInterview Question of the Week #038 – What is Left Semi Join Showplan Operator?
It is very common of interviewers to ask questions which are a bit off and sometimes not used in daily life. Â Here is such question I heard the other dya. Question: What is Left Semi Join Showplan Operator? Answer:Â There are few interesting kinds of joint operations exists when execution…
Read More
SQL SERVER – How to Restore Corrupted Model Database from Backup?
Another email from one of my blog reader, which made me think about the incorrect information which is available on the internet. Hi Pinal, I have corruption in model database and due to that SQL Service is not able to start. Here are the messages in SQL ERRORLOG 2015-09-23 21:45:07.00…
Read MoreSQL SERVER – Failed Rule “Valid DSN” and “Valid Database compatibility level and successful connection”
I always try to keep myself up-to-date with latest release of SQL Server. As a part of that I wanted to upgrade my SQL Server 2016 CTP2.2 to CTP2.3 version. While doing in-place upgrade I was blocked with few error and I was not able to proceed. Here is the…
Read MoreSQL SERVER – Finding If Date is LastDay of the Month
As I said many times before SQL Server does not stop amazing me continuously. It does not matter how many questions and issues I have come across so far there are always new things to learn. Here is the question which I was asked – How do we know if…
Read MoreSQL SERVER – Scope of ERROR_MESSAGE
SQL Server supports Error handling efficiency. You can do this with the help of TRY and CATCH blocks. If there is an error you can get the exact error message using the system function ERROR_MESSAGE(). I will demonstrate it using the following code BEGIN TRY SELECT 1+'SQL' AS RESULT END…
Read More