Skip to main content

Oracle - How to insert a string longer than 4k using C#

And this is another PITA sponsored by our good friends of Oracle ;)

After being struggling whit this issue for a whole day, I finally figure it out. There is a bunch of posts on the web saying that you should change the column type on the table from let’s say LONG to CLOB or stuff like that… but I have tried it and it has no effect if you are working with C# (maybe make sense if you are working with PL. I’m not sure, haven’t test it). The thing is even if you change the column type, you’ll still get an error saying “the string literal is too long…” The way to insert strings larger than 4K into Oracle databases is using bindings. And yes, you can insert 4k plus strings into LONG columns, there is no such 4k limit. This is how you do that:

* I skip error handling, disposing objects, etc… just for brevity, of course you shouldn't ;)

Another interesting thing that almost every posts got wrong is that you don’t have to specify the parameter type, the library will choose the right type for you. So don’t waste your time on that.


Popular posts from this blog

How to create MS Word documents from Office templates using C#

The OpenXML SDK allows you to do pretty much anything you want with office files such as Excel, Word, etc… While many people like this library, I found it complex, unintuitive and poorly documented, not to mention the awful xml format that uses under the hood to represent the documents, styles, etc. So I decided not to use it and build my own solution. If you, like me, don’t like that library, you will find in this post an alternative approach to build word documents from templates using c#.
A neat trick to work with Office is to use the macro recorder to understand how things work. The macro recorder allows you to start a macro, do something by hand, stop it, and then take a look at the generated VBA code. Once you do this, you are pretty much set.
This is how it looks the template I’am going to use.

Note: save the file as a Word template (.dotx)
This is the code to create Word documents from C#:

By running the code, you should get a document that looks like this.

Note that the font, forma…

Printing html using the embedded web browser control

In this post I’ll try to answer some questions about the web browser control and provide some workarounds for known issues involved in the printing process.
I'm assuming that you have some experience with the web browser control and basic knowledge of COM and hosting APIs. So I’m not going to cover those topics.
At the bottom of this page I’ve added the links to download a small library I wrote that takes care of printing HTML and a demo app so you can try it out without having to write any code by yourself.
Using the code The HtmlPrinter class will allow you to print html from an URL or just passing the html as string, you can also specify the title and the number of copies you want to print. The code may look something like this: Now that we know how to use the API let get answer some questions.
Why my app crashes when I try to print multiple copies of a page? Well, apparently when you send a lot of print commands to the web browser control, there is a lot of COM crap in between that l…

WinForms, paging the DataGridView the right way

I know this may sound like old history, but in the enterprise world there is still a lot of WinForms development. Just a couple of days ago, I had to implement a custom DataGridView capable to work over a butt load of data (100K+ records) and keep responses times acceptables.
I thought paging will be a good way to go, and as WinForms is pretty old nowadays, I supposed it will be easy to find a couple examples on the web.
While in fact I found examples, all of them were incompletes and/or they wouldn't perform well in real world apps... So I decided to roll my own component and post it online. Hopefully, someone else will find it useful ;).

The bread and butter of this solution relies on LINQ and deferred execution. As LINQ takes care of all complicated work, it was quite easy to implement.
This component also supports conditional format, sorting and some search capabilities, but in this post I will concentrate on paging only (I'll cover the rest of the features in future posts)…