The Bit Bucket

Percent Encoding (also known as URL Encoding) is a technique for encoding the values in strings that are not able to be directly represented, according to the rules for the target location. For example, not all characters are permitted in URLs.

Percent encoding a T-SQL string is also useful when working with XML. For example, one common method for splitting strings is based on the use of XML PATH but if you try to use those types of string splitters with strings containing, say, percent signs, you’ll find they just don’t work.

2018-01-31

When many SQL Server customers are asked why they haven’t kept up to date with either SQL Server versions, or more importantly, patches to SQL Server, the answers usually boil down to two reasons:

• They are just slack
• Their vendors won’t support the later version or patch level

Many SQL Server application vendors don’t keep up to date with testing of their applications on released versions or patches for SQL Server.

2018-01-30

I spend a lot of time reviewing SQL Server T-SQL code from developers. There are quite a few issues that I see regularly, and one of these relates to UNION.

In SQL Server, a UNION statement is actually a UNION DISTINCT (but we’re not allowed to put the word DISTINCT in the syntax). The alternative is a UNION ALL. Often a UNION ALL is what’s needed, and using a UNION leads to unnecessary performance problems.

2018-01-29

I keep doing work at sites where none of the database code is stored in version control (source control) systems. I keep wondering why that is.

At a recent site, all the source code was in individual files just sitting in a single folder. That’s just not sensible.

I’m left wondering why it is that almost every team that I see working with higher-level languages just assumes that some form of source control would be used, yet it’s almost the opposite when I’m working with data teams.

2018-01-26

It’s likely that everyone who uses SQL Server Management Studio (SSMS) knows how to tell how long a query ran for. You can see it in the bottom right of the status bar when a query finishes.

But one question that often comes up with a long-running query is when did my query finish?

That’s not in the status bar and many people don’t seem to be aware that you can find it out.

2018-01-25

Today’s post is about one of our free SDU Tools that helps you with what you’d think would be a simple task in T-SQL but isn’t.

TrimWhitespace is used to remove leading and trailing whitespace characters in T-SQL strings. As well as spaces, it will remove carriage returns, linefeeds, and tabs.

You can see its action in the image above.

You can also see it in action here:

2018-01-24

Case sensitivity in comparisons is an aspect of computing that I’m surprised is still so widespread. I can’t say it more clearly than this:

It’s a pox on computing and needs to be eradicated.

I’ve recently been working at a site where a new case-sensitive SQL Server system is being implemented. I cannot begin to describe what a poor idea I think this is.

In the end, all that a case sensitive system allows you to do is:

2018-01-23

In short: YES

(In contradiction to Betteridge’s Law of Headlines)

Every now and then, customers ask me if they really need to run DBCC CHECKDB. There was even a question that came up about this on a private mailing list full of people who really should already understand why. There is no mystery here.

DBCC CHECKDB checks the database for physical readability (are the pages intact and can they be read from the I/O system). This makes people wonder that if the I/O subsystem is already doing this, why does SQL Server need to do this?

2018-01-22

For many years now, it has been important to script the configuration and deployment of systems, particularly virtual machines. Infrastructure as Code is now a common requirement but as the required configuration has become more complex, scripting in language like PowerShell has become more difficult.

It’s all very well to write code to add say a network adapter, but how do you check the current state of the machine?

• Did that adapter already exist?
• Is something else using the IP address?
• How do you write a script to a cater for all the situations?

This leads to ever-more complex code and this is where my concerns start. Writing code for creating infrastructure needs the same discipline that writing any other code does. This includes code quality, coding conventions, error handling, source code control and versioning. Yet, who is writing this code?

2018-01-19

Two key combinations used by SQL Server T-SQL developers every day are Ctrl-C and Ctrl-V for copy and paste.

But many users of SQL Server Management Studio (SSMS) don’t realize that it has a clipboard ring and can deal with several objects in the clipboard at the same time.

Let’s see an example.

In this screen shot, I’ve opened a query window with the source code of the AnalyzeTableColumns procedure from SDU Tools.

2018-01-18