Just the other day I was busy during a performance tuning exercise I explained to the team of DBA that how much log file is critical and important for their performance. Once I was explaining the importance and role of the LDF file in the performance, one of the DBA from the team asked me question about what would they do if they somehow lose the LDF file or just have corrupted log file which they do not care now. Well, I though it was a very important question and I believe it can be a very good interview question as well. Let us learn about how to attach the MDF data file without LDF log file.
SQL SERVER – Unable to cast object of type ‘System.DBNull’ to type ‘System.String’. (Microsoft.SqlServer.Smo)
When you are driving on a highway, you look forward to the sign boards give you guidance while you are busy driving. These sign boards tell you when your exit is approaching and how you should be dealing with the same. I consider such sign boards inside SQL Server as “Error Messages”. I rely on them so heavily to give me insider information to a possible solution. Not always are these messages super easy to understand. Take for instance the following message. While trying to create a database on my lab server, I got below error related to System.DBNull:
SQL SERVER – Script level upgrade for database master failed because upgrade step sqlagent100_msdb_upgrade.sql encountered error
Sometimes I feel that one error can be caused due to multiple reasons and there are different ways to solve it. I already have two blogs for the error message. As they say, there are is no silver bullet when it comes to solving some of the issues. SQL Server might through a generic message, but it all lead to the same problem related to master database:
How to Use Zip With SSIS? – Notes from the Field #130
[Note from Pinal]: This is a 130th episode of Notes from the Field series. In this episode we are going to learn something very simple but effective about SIS and Zip. This subject is not very much discussed about and hardly there are many information about this subject available. In this episode of the Notes from the Field series database expert Kevin Hazzard explains the how to use ZIP with SSIS. Read the experience of Kevin in his own words.
SQL SERVER – Error Fix: Msg 13601 Working with JSON Structure
As you new versions of SQL Server come, the amount of capabilities just increases exponentially. It is tough to keep up in pace with the innovations and learning that one needs to go through. I have in the past written few articles around working with JSON over the blogs earlier. These games of playing with the new capabilities will show up tons of errors as we are not completely aware of what is possible. These experiments lead you from learning to another.
Recover Lost Data Using the Transaction Log Files
Every now and then, experienced SQL Server DBAs as well as the SQL Server rookies find themselves in the unpleasant situation when some important data has been changed or lost with the monumental task to solve this in the most efficient way. Regardless of the change source – was it an internal or external user, the intent behind it – unintended mistake or a malicious change, or even the exact nature of the change – update, delete, drop or something else, database administrators are faced with the task to recover the lost data and enable users to continue using the database as if the recovery was never required by providing the data recovery. Let us learn about how to recover lost data using the transaction log files.
SQL SERVER – FCB::Open failed: Could not open file Path for file number 2. OS error: 5(Access is denied.)
I assume a number of times when the machine is booted up, I am most likely to hit the Management Studio to work on some script or the other. But sometimes strange things happen and I get all sorts of error. There might be tons of reasons why SQL Server is not able to start. This blog is a result of a quick consulting engagement with one of my clients where I faced OS error.
Moving TempDB to New Drive – Interview Question of the Week #077
Midnight at 1 AM, I received a call from my customer where I have earlier worked on performance tuning project. As soon as I picked up the phone call the first statement from my friend was about TempDB and it was as follows:
“We should have followed your advice, the TempDB is full, now help us fix it.”
SQL SERVER – Fix Error – 948 A downgrade path is not supported. The database cannot be opened because it is version.
These past weeks the number of errors I have been getting when attaching a database has been far too many. But the best part of this learning experience is that I get to write about them one after another. There are no right or wrong answers sometimes, but am learning every time. Here is an error which is related to a downgrade path not supported. I received while I was trying to attach database using below command:
SQL SERVER – Identifying InMemory OLTP Hash Collisions
It is about a few weeks back that I wrote about how InMemory OLTP Hash Collisions can happen and how it can affect performance. Here is a recap of that post for your reference and do check the same before proceeding reading this blog post.