i am trying to store large data more than 255 characters in a string datatype but it truncates after 255. how can i achive this basically i need to pass this data to database
C# strings do not have any particular character limit. However the database column you are writing to may have a limit. If you are storing large amounts of data, you should use a BLOB column instead of an ordinary varchar type.
StringBuilder class
Like they said the string class is not limited, but you can do this for large strings. I feel it handles them better.
StringBuilder sb = new StringBuilder();
sb.append("Some text...");
sb.append("more text...");
sb.append("even more text!");
sb.toString();
Okay, it sounds like you have several different technologies involved - Excel, XML, databases etc. Try to tackle just one at a time. First read the data out of Excel, and make sure you can do that without any truncation.
Write a small console app which will read the value, then write it to the console - and its length. If that works, you know the problem isn't in Excel.
Next you can write a small console app with hardcoded input data (so you don't need to keep using interop with Excel) and write the XML from that, or whatever your next stage is.
Basically, take the one big problem ("when I read data from Excel and write it to the database it truncates long values") and split it into smaller and smaller ones until you've found what's wrong.
The string type does not limit strings to 255 characters. Your database column must be 255 characters.
I know that c# strings can hold much longer data than that. If the truncation occurs on commiting to DB, check the length constraint on ur Db field
The problem lies in the Excel part; .Character has a 255 characters limitation.
To read the complete text from a shape the following VBA syntax would do:
Worksheets("YourSheet").Shapes("Shape1").OLEFormat.Object.Text
Related
I'm currently using SSIS to do an improvement on a project. need to insert single documents in a MongoDB collection of type Time Series. At some point I want to retrieve rows of data after going through a C# transformation script. I did this:
foreach (BsonDocument bson in listBson)
{
OutputBuffer.AddRow();
OutputBuffer.DatalineX = (string) bson.GetValue("data");
}
But this piece of code that works great with small file does not work with a 6 million line file. That is, there are no lines in the output. The other following tasks validate but react as if they had received nothing as input.
Where could the problem come from?
Your OuputBuffer has DatalineX defined as a string, either DT_STR or DT_WSTR and a specific length. When you exceed that value, things go bad. In normal strings, you'd have a maximum length of 8k or 4k respectively.
Neither of which are useful for your use case of at least 6M characters. To handle that, you'll need to change your data type to DT_TEXT/DT_NTEXT Those data types do not require a length as they are "max" types. There are lots of things to be aware of when using the LOB types.
Performance can suck depending on whether SSIS can keep the data in memory (good) or has to write intermediate values to disk (bad)
You can't readily manipulate them in a data flow
You'll use a different syntax in a Script Component to work with them
e.g.
// TODO: convert to bytes
Output0Buffer.DatalineX.AddBlobData(bytes);
Longer example of questionable accuracy with regard to encoding the bytes that you get to solve at https://stackoverflow.com/a/74902194/181965
I have to make a method that exports database data to a file. The software that will process this file requires specific string length - no more, no less. The data that comes in will have less than the required number of characters, but I have to make the length of every column fit that number exactly by addind whitespaces.
Does anyone have an idea how to do this in the most efficient way? The datasets won't be small and the only thing that comes to mind is looping over every table cell, checking the length and then adding up to the required length...
I have an ETL that's saving data to an Excel file. The issue is that the decimals are not being written out for integers. Example:
14.00
is being written out as
14
My code for writing out that line is
loWorksheet.Cells[liRowNum, 5] = lcAmount.ToString("0.00");
When I step through the code, it shows as 14.00, but on the Excel file it is not retaining the decimal places. Is this something that can be fixed in my code or is this an Excel issue? Any suggestions?
I'm quite sure you have to set format for your cells. I can't check right now, but it will be something like
xlYourRange.NumberFormat = "0.00";
You can check this question Set data type like number, text and date in excel column using Microsoft.Office.Interop.Excel in c#
If you really want the data to be displayed literally the way it is in the source file, you have to deal with trade-offs. The simplest way is to format the data as text. You can do this a cell at a time or for entire columns:
loWorksheet.Columns["A:E"].NumberFormat = "#";
The trade-off is it's just text at this point. You can't add, sum, average, whatever.
On the other hands, if your data looks like this:
4.0
4.00
4.000
You can't really keep it as numbers and expect to retain the original format without doing some funny business.
If it's consistently two decimal places, and you know it's going to be, then I agree with #RenatZamaletdinov's solution.
And you might want to consider other strings and what Excel might to do them
0000123 becomes 123
10/23 will probably render as a date, depending on your localization
12345678901234567890 will render as scientific notation probably
These are all avoided if you make the numeric format text (#), but again without knowing what you plan to do with the data, it's hard to say if this is the correct approach.
Wrap lcAmount.ToString("0.00");in a pair of quotes and put an equal sign in front of it. This will prevent excel from overriding the format.
loWorksheet.Cells[liRowNum, 5] = "=" + '"' lcAmount.ToString("0.00") + '"';
Hey Everyone, I am writing some code that makes use of SQL Server CE 3.5 and I am having a very strange problem. I have a string field in one of the tables that needs to store a full file path.
Over the course of trying to fix this problem I have that field set as nvarchar with a max size of 4000, but it is still cutting longer strings that are much shorter than the limit off
for example:
D:\iTunes\iTunes Media\Music\Abigail Williams\In The Absence Of Light\02 Final Destiny Of The Gods.m
This is clearly smaller than 4000 characters, yet it is missing the p3 at the end of the string.
I am using a table adapter to enter the data into the database with the following query:
INSERT INTO [Track] ([Artist_ID], [Album_ID], [FilePath], [LastUpdate])
VALUES (#Art, #Al, #Fp, #LU)
I know that the strings are fully formed on insert because I am using the following code to check:
if(!temp.Filepath.EndsWith(".mp3"))
MessageBox.Show("File Error");
this.trackTableAdapter1.InsertQuery(ArtID, AlID, temp.Filepath, File.GetLastWriteTime(temp.Filepath));
The message box does not get shown, so the string must end correctly on insert.
the query that extracts the data is:
SELECT
*
FROM Track
WHERE Artist_ID=#Artist_ID AND Album_ID=#Album_ID
The involved code is:
foreach (Database.MusicDBDataSet.TrackRow TR in this.trackTableAdapter1.GetAlbumTracks(AR.Artist_ID, AlR.Album_ID).Rows)
{
//if (!TR.FilePath.EndsWith(".mp3"))
//MessageBox.Show("File Path Error");
this.ArtistList[AR.Name].AlbumList[this.ArtistList[AR.Name].AlbumList.Count - 1].TrackList.Add(new Track(TR.FilePath, AlR.Name, AR.Name));
}
Has anyone ever run into this problem before?
Check the XSD file. Specifically, check the FilePath column of your table and look for the max length.
Maybe take a look at the SQLServerCE Parameter Size limitation.
What is the specific maximum length? Is it around 100 chars? (Guessing based on your provided input example).
The 100 unicode chars also matches with D.K. Mulligan's answer. Looking at SQL ServerCE Paramater Size Property
For variable-length data types, the Size property describes the maximum amount of data to send to the server. For example, the Size property can be used to limit the amount of data sent to the server for a string value to the first 100 bytes.
For Unicode string data, the Size property refers to the number of characters. The count for strings does not include the terminating character.
Try bumping the size to see if this is the magic number that is truncating your strings.
I have a text file that has the following format:
1234
ABC123 1000 2000
The first integer value is a weight and the next line has three values, a product code, weight and cost, and this line can be repeated any number of times. There is a space in between each value.
I have been able to read in the text file, store the first value on the first line into a variable, and then the subsequent lines into an array and then into a list, using first readline.split('').
To me this seems an inefficient way of doing it, and I have been trying to find a way where I can read from the second line where the product codes, weights and costs are listed down into a list without the need of using an array. My list control contains an object where I am only storing the weight and cost, not the product code.
Does anyone know how to read in a text file, take in some values from the file straight into a list control?
Thanks
What you do is correct. There is no generalized way of doing it, since what you did is that you descirbed the algorithm for it, that has to be coded or parametrized somehow.
Since your text file isn't as structured as a CSV file, this kind of manual parsing is probably your best bet.
C# doesn't have a Scanner class like Java, so what you wan't doesn't exist in the BCL, though you could write your own.
The other answers are correct - there's no generalized solution for this.
If you've got a relatively small file, you can use File.ReadAllLines(), which will at least get rid of a lot cruft code, since it'll immediately convert it to a string array for you.
If you don't want to parse strings from the file and to reserve an additional memory for holding split strings you can use a binary format to store your information in the file. Then you can use the class BinaryReader with methods like ReadInt32(), ReadDouble() and others. It is more efficient than read by characters.
But one thing: binary format is bad readable by humans. It will be difficult to edit the file in the editor. But programmatically - without any problems.