The perils of double-dash comments [T-SQL]

Posted by jamiet on SQL Blog See other posts from SQL Blog or by jamiet
Published on Thu, 06 Dec 2012 09:21:39 GMT Indexed on 2012/12/06 11:16 UTC
Read the original article Hit count: 437

Filed under:

SQL Server

|

sql server integration se

|

ssis

|

t-sql

I was checking my Twitter feed on my way in to work this morning and was alerted to an interesting blog post by Valentino Vranken that highlights a problem regarding the OLE DB Source in SSIS. In short, using double-dash comments in SQL statements within the OLE DB Source can cause unexpected results. It really is quite an important read if you’re developing SSIS packages so head over to SSIS OLE DB Source, Parameters And Comments: A Dangerous Mix! and be educated. Note that the problem is solved in SSIS2012 and Valentino explains exactly why.

If reading Valentino’s post has switched your brain into “learn mode” perhaps also check out my post SSIS: SELECT *... or select from a dropdown in an OLE DB Source component? which highlights another issue to be aware of when using the OLE DB Source.

As I was reading Valentino’s post I was reminded of a slidedeck by Chris Adkin entitled T-SQL Coding Guidelines where he recommends never using double-dash comments:

That’s good advice!

© SQL Blog or respective owner

Related posts about SQL Server

SQL SERVER – Concat Strings in SQL Server using T-SQL – SQL in Sixty Seconds #035 – Video

as seen on SQL Authority - Search for 'SQL Authority'
Concatenating string is one of the most common tasks in SQL Server and every developer has to come across it. We have to concat the string when we have to see the display full name of the person by first name and last name. In this video we will see various methods to concatenate the strings. SQL… >>> More
SQL SERVER – Concat Function in SQL Server – SQL Concatenation

as seen on SQL Authority - Search for 'SQL Authority'
Earlier this week, I was delivering Advanced BI training on the subject of “SQL Server 2008 R2″. I had great time delivering the session. During the session, we talked about SQL Server 2010 Denali. Suddenly one of the attendees suggested his displeasure for the product. He said, even though… >>> More
Nested SQL Select statement fails on SQL Server 2000, ok on SQL Server 2005

as seen on Stack Overflow - Search for 'Stack Overflow'
Here is the query: INSERT INTO @TempTable SELECT UserID, Name, Address1 = (SELECT TOP 1 [Address] FROM (SELECT TOP 1 [Address] FROM [UserAddress] ua INNER JOIN UserAddressOrder uo ON ua.UserID = uo.UserID WHERE ua.UserID = u.UserID ORDER BY uo.AddressOrder ASC) q ORDER BY AddressOrder… >>> More
How can I detect which version of SQL (eg SQL 2008 or SQL Azure)

as seen on Stack Overflow - Search for 'Stack Overflow'
I need to detect which version of SQL I am dealing with to perorm various tasks, I need specifically detect if I am on SQL 2008 or SQL Azure. How can I do this with detection code written in SQL? >>> More
Putting data from local SQL database to remote SQL database without remote SQL access enabled (PHP)

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I have a local database, and all the tables are defined. Eventually I need to publish my data remotely, which I can do easily with PHPmyadmin. Problem however is that my remote host doesn't allow remote SQL connections at all, so writing a script that does a mysqldump and run it through a client… >>> More

Related posts about sql server integration se

SQL SERVER – Concat Strings in SQL Server using T-SQL – SQL in Sixty Seconds #035 – Video

as seen on SQL Authority - Search for 'SQL Authority'
Concatenating string is one of the most common tasks in SQL Server and every developer has to come across it. We have to concat the string when we have to see the display full name of the person by first name and last name. In this video we will see various methods to concatenate the strings. SQL… >>> More
Oracle releases Java SE 7 Update 7, and Java SE 6 Update 35

as seen on Oracle Blogs - Search for 'Oracle Blogs'
This morning, Oracle released updates to JDK 6 and 7. For more information on these releases see: Security Alert for CVE-2012-4681 Released Release notes Oracle recommends that users apply these updates as soon as possible. Users of Oracle JRE 6 and 7 for Windows (32-bit) and the recently released… >>> More
Cloud and On-Premises Applications Integration using Oracle Integration Adapters

as seen on Oracle Blogs - Search for 'Oracle Blogs'
See how Oracle Integration adapters will continue to provide connectivity and harness information from diverse enterprise applications and technologies—both on-premises and in the cloud on our Exclusive Openworld session - "CON8642 - Cloud and On-Premises Applications Integration, Using… >>> More
Java version indicates SE 6, Java Control Panel SE 8

as seen on Super User - Search for 'Super User'
So I'm trying to get the Java 7 as the default version on my machine, running Mac OS X 10.9.3. When I run: java -version I get: java version "1.6.0_65" Java(TM) SE Runtime Environment (build 1.6.0_65-b14-462-11M4609) Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-462, mixed mode) When I… >>> More
Integration tests in Continuous Integration environment: Database and filesystem state

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to implement automated integration tests for my application. It's a very complex monster. You could say that its database and part of the filesystem are part of its state, because it saves image files in the hard drive, and references to those in the DB. The software needs all those, in… >>> More