We're having some queries in an Azure SQL database that are occasionally running very slowly. The issue has been difficult to properly diagnose, as the same queries will run fine at other times, even when the server is under a similar load.
To help, I'd like to be able to view log information for the server. If I could see a list of transactions, by time, and their outcome (completed, terminated/rolled back, etc) I believe it would be helpful. Several other SQL pages seem to allude to log-files you can access, but since this is an Azure SQL instance, there isn't a physical server I can just download a file from.
I know I can query sys.event_log to see when particular events are occurring (and in fact, I do see a high amount of deadlocks around our problem times), but I'm unaware of any way to see what query's were being handled at the time of these locks.
I'd like to be able to view log information for the server. If I could see a list of transactions, by time, and their outcome (completed, terminated/rolled back, etc) I believe it would be helpful.
The log information you are trying to view is not helpfull.
You can view slowly running queries running using the same manner like on premises using DMV's
You can also enable query store ,which can you show you different stages of query .This i think will help you more in troubleshooting slow queries and is not tied to Premium Databases only
Related
I've been a SQL Azure Database user for some time (over a year). I have a mostly readonly 5GB database that fuels my website. Queries hit the database about once or twice a second, and response times are generally sub 100ms.
There have been a few times when performance for all queries goes down the toilet. Today for example, I awoke to alarms that the database was performing poorly. Simple queries that normally take 30ms are taking over 3 minutes! My load on the server is no greater than usual, so I attribute this decline in performance to my DB sharing an instance with one or more DBs from other Azure users.
To solve this problem, I copy the database to a new instance (CREATE DATABASE NEW_DB AS COPY OF OLD_DB), and point the website to the new instance. All is well until this happens the next time. In about a year's time, this has happened 4 or 5 times.
My question: does anyone have some advice on how to mitigate this? If this is just life under Azure, it's pretty unacceptable.
EDIT: just realized that this question is from 2014. If you're still having issues, the questions and suggestions below may guide you in the right direction. If you've resolved the performance issues, feel free to share how any actions you may have taken to improve performance.
What tier are you on right now?
Reference: http://searchsqlserver.techtarget.com/tip/SQL-Azure-database-recommendations-and-best-practices
Are your users coming from different geographical regions? If so, are you using endpoint monitoring for the web app that accesses your SQL Azure db?
Reference: https://azure.microsoft.com/en-us/documentation/articles/web-sites-monitor/#webendpointstatus
Have you tried reading through the official performance guide?
Reference: https://msdn.microsoft.com/en-us/library/azure/dn369873.aspx
Here's a 3rd-party writeup that mentions "the differences in connectivity behavior or that SQL Azure resources get throttled when you overload the database require you to take such things into account and code your application to handle issues you may not have using traditional a SQL Server application."
Reference: http://searchsqlserver.techtarget.com/tip/SQL-Azure-database-recommendations-and-best-practices
This article requires (free) email signup before reading the full article, but it may help you with some recommendations and best practices.
Hope that helps!
I have a delicate situation wherein some records in my database are inexplicably missing. Each record has a sequential number, and the number sequence skips over entire blocks. My server program also keeps a log file of all the transactions received and posted to the database, and those missing records do appear in the log, but not in the database. The gaps of missing records coincide precisely with the dates and times of the records that show in the log.
The project, still currently under development, consists of a server program (written by me in Visual Basic 2010) running on a development computer in my office. The system retrieves data from our field personnel via their iPhones (running a specialized app also developed by me). The database is located on another server in our server room.
No one but me has access to my development server, which holds the log files, but there is one other person who has full access to the server that hosts the database: our head IT guy, who has complained that he believes he should have been the developer on this project.
It's very difficult for me to believe he would sabotage my data, but so far there is no other explanation that I can see.
Anyway, enough of my whining. What I need to know is, is there a way to determine who has done what to my database?
If you are using identity for your "sequential number", and your insert statement errors out the identity value will still be incremented even though no record has been inserted. Just another possible cause for this issue outside of "tampering".
Look at the transaction log if it hasn't been truncated yet:
How to view transaction logs in SQL Server 2008
How do I view the transaction log in SQL Server 2008?
If you want to catch the changes in real time, I suggest you consider using SqlDependency. This way, when data changes, you will be alerted immediately and can check which user is using the database at the very moment (this could also be done using code).
You can use this code sample.
Coming to think about it, you can establish the same effect using a trigger and writing ti a table active users. Of course, if you are suspecting someone is tempering with data, using SqlDependency might be a better way to go with, as the data will be stored outside of the tampered database.
You can run a trace, for example a distant profiler trace, that will get all SQL queries containing the DELETE keyword. This way, nobody will be aware that queries are traced. You can also query the default trace regularly to get the last DELETE commands: Maintaining SQL Server default trace historical events for analysis and reporting
All-
I'm trying to determine which SQL databases are currently being used the most (as well as what applications are requesting information from them).
Is there a log analyzing tool? Or something built into SQL server that could help me achieve this?
Ideally I'd like to show a map of server usage and understand which applications are actually hitting them.
Thanks!
sys.dm_db_index_usage_stats shows exactly how many time each index/table was read/scanned/updated since the server started up. This is the most important piece of information since everything else (IO, RAM, CPU) can be ultimately traced to these operations. The one information not revealed from here is blocking and contention, for which a good starting point is sys.dm_os_wait_stats. And finally there is sys.dm_exec_query_stats which will drill down to the individual query CPU and execution times.
If you right-click on the server in Management Studio you will see a 'Reports' option. There are a lot of built in reports which might give you what you need (the 'Server Dashboard' report in particular shows which databases are consuming the most CPU and I/O).
Alternatively the Profiler provides a lot of (perhaps too much) valuable data.
I have an ecommerce application that I believe is not properly caching all of our images and so I would like to capture all the queries that are occurring against our images table.
I need to be able to do this without installing anything or adding any code to the solution.
Can this be accomplished with SQL Profiler or another tool that does not require code modification?
The SQL Profiler is indeed the right tool for this.
You can attach it to your database, set some filters (for example, the text should contain the table name) and what events to log and off you go.
SQL Profiler will capture the queries as you have identified, you could also inspect the query cache, but it would not necessarily have all of the queries against that table still in cache, so should not be relied on.
I often find myself writing one off queries to either answer someone's question or trouble shoot something and I would like to be able to quickly expose the on demand refreshable results of the query graphically so that I can share these results to others without having to go through the process of creating an SSRS report and publishing it to a reporting services server.
I have thought about using excel to do this or maybe running a local SSRS server but both of these options are still labor intensive and I cannot justify the time it would take to do these since no one has officially requested that I turn this data into a report.
The way I see it the business I work for has invested money in me creating these queries that often return potentially useful data that other people in the organization might want but since it isn't exposed in any way and I don't know that this data is something they want and they may not even realize they want this data, the potential value of the query is not realized. I want to increase the company's return on investment on all these one off queries that I and other developers write by exposing their results graphically so that they can be browsed by others and then potentially turned into more formalized SSRS reports if they provide enough value to justify the development of the report.
What is the fastest way for me to take a query and turn it into a refreshable graph of the results set?
Why dont you simply use what you may already have. Excel...you can import data via an ODBC / Oracle / SQL Connection. Get Data..and bam you can run the query and format it right in the spreadsheet and provide sorting etc. All you need to supply is the database name and user name and password to connect to the db.
JonH is right regarding Excel's built in ODBC support, but I have had tons of trouble with this. In my case, the ODBC connection required the client software to be installed so that it could use the encryption methods, etc. Also, even if that were not the case, the user (I believe) would still have to manually install and set up an ODBC connection.
Now if you just want something on your machine to do the queries and refresh them, JohH's solution is great and my caveats are probably irrelavent. But if you want other users to have access, you should consider having a middle-man app (basically a PHP script, assuming a web server is an option for you), that does a query, transforms the results into XML, and outputs it as "report-xyz.xml". You can then point anybody running a newer version of Excel to that address and they can very easily import the data into Excel with no overhead. (basically a kind of web service).
Keep in mind, I don't think you should have a web script that will allow users to make queries to your Database server! You would have some admin page where you make pass the query in and a new xml file with the results gets made. So my idea is also based on the idea that you want to run the same queries over and over without any specifics passed in. (if that were the case, I'd look into just finding a pre-built web services bridge for your database that already has security features built in. Then you could have users make the limited changes allowed.)