TSQL2sday is a monthly SQL Server blogger event started back in late 2009 by Adam Machanic (blog | twitter). For more info on its beginning and purpose see the origin of TSQL2sday. Each month a different SQL Server blogger is the host (announces the theme and compiles a recap). This month’s event is hosted by Erin Stellato (blog | twitter) and the selected theme for this month is “A Day in the Life”.
Erin challenged us to track what we did in our jobs for a specific day and write about it. This is great because I often have trouble explaining to others (especially non-IT folk) what my title of SQL Server Service Engineer really means. However, as this exercise is just supposed to cover a single day, this is just a small sample of what I do. There is no such thing as a “normal” day for me. Sometimes my tasks are based on the “crisis du jour” prioritization method, and sometimes I can actually follow the team work plan. The variety in my job is one of the things I like about it. So here goes…
Unless, I have an early morning meeting with global colleagues, my day nearly always begins with processing email. Since I work in a global organization in the region whose workday is last to begin, even if I’d cleared my Inbox the day before, I always open my mailbox to encounter new emails from European and Asia-Pacific colleagues who have already completed or are wrapping up their workday. In that sense, this day starts out as just a normal day (no early meetings!).
Unfortunately for this write-up, it appears that summer time may be impacting my email load in a positive sense as I have only a handful of emails and only as a cc on a couple of subjects which one of my teammates is handling. One of the issues has to do with deploying SQL Server Enterprise Edition versus Standard Edition and licensing implications for the customer. My team is comprised of technical experts – we can tell the customer if what they are trying to do requires a specific edition of SQL Server to use the requested feature, but we are not involved in the licensing agreements between Microsoft and each customer. That is for others to figure out!
Email done and no looming crisis for today, I can get back to the task I’ve been working on previously – writing an automated process to rollout multiple T-SQL Scripts to multiple instances using PowerShell. These are the scripts which update the standard tables and stored procedures in the admin database we install on all instances along with a set of SQLAgent jobs which the operational DBAs use for system maintenance. Every so often, we need to rollout updates to these objects. Our current automated process for doing this (which was developed for SQL 2005) isn’t as automated as we’d like it to be. We have since created a CMS and are utilizing registered groups to run various processes (like EPM) and now want to extend that concept to this activity as well. I’m thinking within a couple of hours I can write a script to save our operational DBAs literally hundreds of man-hours. Easy, right?
If you’ve worked with PowerShell any at all – or any programming language for that matter – you know there is always more than one way to write a process to accomplish the task at hand. The challenge is in finding the most efficient way that gives you what you want. Our old script to run a set of .sql files was written in VBScript and called the sqlcmd utility. I figured I’m writing this in PowerShell, I’m using Invoke-Sqlcmd to get the list of instances from the CMS, I can use the Invoke-Sqlcmd cmdlet as shown in BOL in the second example and it will work just like sqlcmd. Wrong! It seems that example only works if you are running a SELECT statement in your InputFile. This particular set of .sql files should have no output unless it is an error and in my test I have a script which I know produces an error – but my output file is empty.
I try various parameters such as -ErrorLevel and -SeverityLevel and I even use -Verbose to no avail – still nothing is piped to my output file. I consult with my team mates to see if they tried this before; I search for examples on the Internet and the best I can find in one of the forums was someone else encountering the same thing, but with no solution for me. I can be stubborn some times and I’m not about to give up yet – after a couple of hours of struggling – I fire off an email to my SQL PowerShell buddy Allen White (blog | twitter) asking for his input – can I do what I’m trying to do with Invoke-Sqlcmd or should I revert to calling sqlcmd?
While waiting for Allen to respond, a couple of more emails have hit my Inbox. Yea! It appears that our request to rebuild one of our team’s test servers has been completed. We try not to do this too often, but part of engineering is writing scripts \ installing \ testing \ uninstalling \ enhancing scripts…repeat; over the course of time sometimes things get so messed up from all the testing (and occasional bad script) you just have to start over with a clean image. This is now a box we plan to use for testing our processes on SQL Server 2012.
It doesn’t take long before I have a reply from Allen – I hope he doesn’t mind if I quote him:
I honestly believe that it’s best to use the tool that best suits the task, so I’d use sqlcmd here, because it works the way you want it to.
Thanks Allen for the reminder not to use a hammer when a screwdriver is what you need! Sometimes, a hammer is all you have, but not in this case.
Now, it’s time for lunch. I head down to the cafeteria with my team mates and join other colleagues at our usual table. I don’t hang around too long chit-chatting as I want to get back to my desk and switch out my code and test so I can announce success at our afternoon team meeting.
Remember earlier what I said about more than one way to do something? Now, I have to decide how to go about calling sqlcmd.exe from PowerShell. I need to specify variables to all the parms based on the target instance and input file to execute – and the output filename and location is dynamically determined as well based on the target instance and input filename. I start with looking at Invoke-Command, then move to Invoke-Expression, but I’m still not getting my output file like I want it and I’m not able to detect if sqlcmd experienced an error to report in my general execution log. I have an example using [diagnostics.process]::start($exe,$args).WaitForExit() that seems to be getting me close to what I want, but now it is time to break for my afternoon meeting.
I’m the Technical Team Lead for a team of three. We each have our areas of specialization within the overall work plan, but try to keep each other in the loop so we can back each other up at any time. As needed (usually every 1-2 weeks), we meet formally to update the work plan, assign/reassign new/old tasks if needed, catch each other up on what we’ve each been working on and brainstorm areas for improvement. This is one of those meetings and since last week was a holiday week and we didn’t meet, we have a lot to catch up on. The nice thing about a team is having others to bounce ideas off of and this is what I do with my frustration in finding the exact syntax I need to be using to get the results I want from calling sqlcmd inside PowerShell. The next thing I know, one of my colleagues has done their own search and found a code example – I look and express skepticism as it is very much like what I’m already doing, but with one key difference that might make a difference; what can it hurt to try?
We continue to discuss how far we want to take this initial rewrite of our update process. We are also in progress of redesigning our whole automated install process and ultimately we want the update process to utilize what we are putting into place there. However, we have a more immediate need to have the operations team rollout some updates and decide that version 1 of the update process will do no more than we have already in place today (in terms of reporting), but it will be automated such that the DBAs only need to review the central output file for any problems. Selection of the systems requiring an update into a special CMS group can be done in an automated fashion as well as scheduling the update itself in SQLAgent. We decide to make further enhancements for logging the process’s results into a central table in a future version.
Our meeting continues with more brainstorming about the consequences of developing an install and configuration solution for SQL Server which can account for multiple versions and differing customer standards (e.g. install locations). We plot out on the whiteboard differing ways we can handle this – probably the umpteenth discussion like this that we’ve had; but each time we come in with new experiences and thoughts from what we decided previously and in some cases started trying to implement and we are therefore continually refining the solution. We are becoming more confident that we are developing a standardized, but flexible solution which is also more sustainable across multiple versions of SQL Server than our existing process.
The meeting concludes and although I’m anxious to try the code snippet my colleague found, it is really time for me to head home. I arrived at the office much earlier this morning than my normal start time trying to beat the rain and now I need to try to get home before the next round hits. There is some flooding already occurring around town. Working further on this script can wait until later. I know that once I do get started back on it, I won’t stop until I have it totally finished. That’s my life!
I probably learned more today in trying all the ways that didn’t work the way I thought they would than if the first code I tried had worked. This experience will pay off later, I know.
Today was an “Edison day”:
I am not discouraged, because every wrong attempt discarded is another step forward.
I have not failed. I’ve just found 10,000 ways that didn’t work.
P.S. I did finally get the script functioning the way I wanted the following day and it will save our operations team hundreds and maybe even thousands of hours. This is what I do!
Filed under: PowerShell, SQL Server, SQLServerPedia Syndication, T-SQL Tuesday | Tagged: Automation, CMS, Installation, PowerShell, SQL Server, TSQL2sday | 3 Comments »
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