I’ve placed some controls onto a page dynamically, and was having trouble accessing them in the code behind. There were several complications – they were inside a place holder, inside a master page. Not my favorite technique, but business needs dictated it.

After a while I stumbled across the code to make it work, and I wanted to record it.

HTML:

and the code behind:

John Adams had written to his wife Abigail during the debate of the Declaration of Independence:

"The second day of July, 1776, will be the most memorable epoch in the history of America. I am apt to believe that it will be celebrated by succeeding generations as the great anniversary festival. It ought to be commemorated as the day of deliverance, by solemn acts of devotion to God Almighty. It ought to be solemnized with pomp and parade, with shows, games, sports, guns, bells, bonfires, and illuminations, from one end of this continent to the other, from this time forward forever more"

Recently I was trying to troubleshoot an MSIEXEC install (you know, where you see MyInstallName.msi in the folder) that wasn’t really giving an error message, and wasn’t logging anything either.

I stumbled upon KB314852 that details how to get the MSIEXEC app to use verbose logging. It applies to XP, but worked fine in Server 2008

http://support.microsoft.com/kb/314852

Enable Windows Installer Logging by Adding Registry Entries
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756  (http://support.microsoft.com/kb/322756/ ) How to back up and restore the registry in Windows

Start Registry Editor (Regedt32.exe), and then create the following path and keys in the registry:
HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\Installer

Reg_SZ: Logging
Value: voicewarmup

The letters in the value field are the options that are available to use with Windows Installer logging. You can use the options in any order. Each option turns on a specific logging mode. For MSI version 1.1, the function of each option is as follows :
v - Verbose output
o - Out-of-disk-space messages
i - Status messages
c - Initial UI parameters
e - All error messages
w - Non-fatal warnings
a - Start up of actions
r - Action-specific records
m - Out-of-memory or fatal exit information
u - User requests
p - Terminal properties
+ - Append to existing file
! - Flush each line to the log

* - Wildcard, to log all information except for the v option. To include the v option, specify *v.
It is recommended that you use this service only for troubleshooting. Leaving the service turned on creates a new Msi*.log file every time you use the Add/Remove Programs tool in Control Panel. This activity adversely affects system performance and disk space.

This works in SQL 2008 and doesn’t in SQL 2000, not sure about 2005

We all have to work with ‘black box’ applications sometime – the kind that has a database with tables and stored procedures that you can’t see into but you still have to work with it.

I had a case like that today, the parameters that I was sending to an encrypted stored procedure were not matching up. Usually that’s a versioning issue. Here’s a handy piece of code that will show you all the parameters in a stored procedure

I’m writing a new web site (which I hope to announce soon) and I need to use a dynamic where clause. The user is going to enter some filter conditions on the web site and the data that they see will be filtered by that criteria. I’m using the RadFilter control by Telerik; it basically gives me the complete where clause.

So, I have a something like

Select * from myTable Where @WhereClause

Of course, that’s not valid SQL. What to do? In the end, I’ll have to use my least favorite solution, dynamic SQL using the EXEC command. I’ll change the statement above into

DECLARE @sql varchar(1000)

SET @sql = ‘SELECT * FROM myTable WHERE ‘ + @WhereClause

exec(@sql)

Ug. At anyrate, the best advice that I could find on the subject was here: http://sommarskog.se/dyn-search.html, I didn’t want to lose the reference so I’ll blog it.

This is a short primer on why indexes are important in SQL Server. I spend most of my day writing code, usually modifying accounting systems. These systems have lots of tables and lots of stored procs and can be kind of daunting. But the people that wrote them optimized them for getting data in, they didn’t spend much time on getting data out… that’s were we come in.

I’m going to show you a quick example on the benefits of writing an index on your stored procedure. But don’t overdo it, too many indexes can be just as bad as no indexes…

In order to show you the benefits, we’ll hook up SQL Profiler and look at what’s happening behind the scenes as our queries run. We’ll also configure SSMS to show us the Actual Execution Plan by clicking on Query > Show Actual Execution Plan

We’ll start with a small query against the customer table:

This produces (in my sample database) 577 lines, and the execution plan looks like this:

In Profiler, we see this:

Note that the query did 124 reads to retrieve the query.

Now, we’ll create an index:

Note that the index is on CUSTNMBR, but we’ve included the CUSTNAME field also. We call this a ‘covering’ index. The index has all the data that SQL will need to return the dataset… SQL won’t even have to look at the actual table. This particular table is very wide, it has quite a few fields. Not having to read the actual table is quite a benefit.

So, now we run the query again and our execution plan changes to this:

Note that we do an Index Scan instead of a Table Scan. Table Scans should scare you. In most cases they’re very bad. (the exception would be on small tables where it doesn’t matter anyway)

To prove our point that we saved some time, we’ll look at Profiler:

Not that our duration is now 4 milliseconds, and we only had 9 reads. It’s easy to see that a reduction in reads from 124 to 9 would have quite an impact on large datasets.

When you create a web site in ASP.NET the form tag is included for you. This issue is magnified if you use master pages (who doesn’t?).

The issue is that the code that you get from PayPal has a <form> tag in it, and you can’t nest form tags. So your code doesn’t post correctly when the user clicks ‘Buy Now’.

Here’s a real easy way around that. There are two ways you can do this, as a link from the <HTML> code, or as a Response.Redirect from the code behind. The link will be less work, but also less flexible.

From the HTML, code something like this:

If you’ll compare the above to the code that you got from PayPal, you’ll see that we converted the <input> tags to be parameters in the query string.

From the code behind it looks like this:

Here’s a list of all the arguments (not guaranteed to be complete or correct, you’ll want to check with PayPal for complete information)

Argument                Description
business                Email address associated with seller's PayPal account
quantity                Quantity of items being sold
undefined_quantity      Allows user to edit quantity
item_name               Name of item
item_number             Optional item number
amount                  Price of each item (without currency symbol)
undefined_amount        Allows user to edit the amount (good for donations)
shipping                Price of shipping
currency_code           Code for type of currency (Default appears to be USD)
first_name              Customer's first name
last_name               Customer's last name
address1                Customer's first address line
address2                Customer's second address line
city                    Customer's city
state                   Customer's state
zip                     Customer's zip code
email                   Customer's email address
night_phone_a           Customers telephone area code
night_phone_b           Customers telephone prefix
night_phone_c           Remainder of customer's telephone number

Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding

When clicking ‘Design’ in the SQL 2005 SSMS

I’ve Googled this in the past and got nothing, but today I hit on this piece of code:

I’m a little skeptical about what it does or why it works but this error slows me down so much I’m willing to try anything. It seemed to work (after closing and opening SSRS)

We’ll see what happens the next time I find this problem.

I’ll keep you posted.

This piece of code will show how to serialize a DataTable to a string, where it can be saved to disk, and then how to read that string back into a DataTable again. Actually, we’ll have to use a DataSet to read the string (in XML format) back in, if you use a DataTable you’ll get:

DataTable does not support schema inference from Xml

Oddly, the DataSet works just fine

There are code comments for each line below, you should not have any trouble with it.

Here's a primer for the jargon, and an opinion about what's important. This was written in May 2011… so it should be valid for… 2 more weeks <smiles>

1. Operating System: They're all going to be Windows 7, but 64bit is much faster. The 'information highway' inside the PC is twice as wide as 32bit. It's like having a hose twice as big, or a road twice as wide. More stuff can flow.

2. CPU. This stuff confuses me. CPUs play a big part in the price, there are lots of differences. Cheaper PCs have slower CPUs. Pick a price point ($399, 499) and try to get the best for the money.

3. Screen size: Personally, I have 4 monitors. Really. It's easier to work on a bigger screen. Same as above. Pick a price point and get a better one.

4. Memory (ram). Windows 7 requires 2gb, and that should be fine. More memory allows you to have more programs open at once; 4gb would be great.

5 Hard drive space (not the same as RAM). RAM goes away when you turn the computer off (think: husband’s memory), the hard drive is magnetic media like a VCR tape, it never erases (think: wife’s memory). More hard drive space means you can store more stuff on your computer. More programs; these days it means more photos and more music. I have 9000 photos to date (8 gb of storage) , and about 80 CDs (5 gb). So,  even a smaller 320 gb drive should do.

6. CD (optical drive). You need this. A DVD is almost always included anyway. (think: watching movies in the airport)

7. Web Cam: I bought my wife’s laptop without one because I didn’t think we’d need one. She’s always taking mine now to Skype with the grandkids. If your kid is going away to college, be sure to get a web cam

8. Last is weight. People don’t usually lug these things around much, unless you’re a travelling salesman. So this might not be so important. But it’s something to think about. Lighter usually means a smaller screen, less battery life, and more expensive. Everything’s a trade off.