Saving an image to SQL Server 2008? - sql

I have this:
Create Proc CrearNuevoImagen
#imagen image
AS
INSERT INTO
Imagenes(imagen)
VALUES(
#imagen
)
I see that #imagen is of type 'image'.
My question is save that I have an .jpg image, on my front-end (my asp.net website code), how could I convert the .jpg image to fit into the 'image'-type column? Or does the SQL Server automatically do this for me?

Save your image object to a MemoryStream. Then you can take the byte array out of the memory stream and pass that to SQL Server to save it in your "image" or "varbinary" column.

The image column type is just a binary container; SQL Server doesn't interpret or modify the data you store there at all.
See http://www.informit.com/articles/article.aspx?p=377078

The IMAGE type is just a name for a type that can store a byte array. It is now deprecated and you should use the VARBINARY(MAX) type instead. Saving JPG files into the back end database is actually a bit more complex if you care about performance, because of the need to avoid these relatively large files to be copied into memory. Have a look at Download and Upload images from SQL Server via ASP.Net MVC for an example of efficient streaming of image files stored in SQL Server BLOB fields.

Related

Import and display a jpeg from a SQL Server database using r

Work has asked us to import a series of jpeg files from a SQL Server database for display on a dashboard product we have. We are using R to query our db and build our dashboards so we need to be able to import the images from SQL Server and display them (or at least export to a local system folder).
We can pull down and display standard table information like File Name, File Size, File Type, and File Data <raw>, but we are having a hard time understanding how to extract and display the jpeg files.
I know they are stored in the database in a varbinary column types, but the standard read/writeJPEG() doesn't seem to like anything without a file path, for example pulling the data directly from the SQL Server database into r.
Tried pulling a single file for export to local folder, but same problem with loading the image.
Any suggestions on how to proceed?
The jpeg::readJPEG function says it can read from raw vectors and you seem to have raw vectors in your data.frame. So try something like
jpeg::readJPEG(dd$FileData[[1]])
For something reproducible, here's an example that reads a sample image from the jpeg package in as a raw vector and then turns that into an image object
#sample data
fname <- system.file("img", "Rlogo.jpg", package="jpeg")
filedataraw <- readBin(fname, "raw", file.info(fname)$size)
Now that we've created a sample raw vector (like the one that's presumably stored in your dataframe), we can parse the image data with the jpeg library
img <- jpeg::readJPEG(filedataraw)
plot(1:2, type='n')
rasterImage(img, 1.2, 1.27, 1.8, 1.73)
If the goal is just to write to a file, you don't need to parse the file as a JPEG at all. You can just write the bytes to disk.
writeBin(filedataraw, "sample.jpeg")

Use SQL to create a text file and save to a varbinary blob file without writing to disk

I currently have a working SQL stored procedure that is using BCP and xp_cmdshell to create a text file on the system disk and then upload that file into a varbinary field in an Attachments table.
What I'm needing to know is if it is possible to do this without writing a file to disk as part of the process?
UPDATED DETAILS
I am using MSSQL 2014 and the intention is to load the text file (a csv file actually) into the database so that other users can download it.
Is Text File is generating only for pusing content into varbinary fields?if so why dont you use simply convert the content directly into varbinary using convert function and push directly the results into table field.
If i am getting wrong correct me pls.

SQL Server: Convert jpeg blob to png

For database migration, I need to convert jpeg image blobs to png blobs. Can this be done pure SQL server way or do I need to have external assemblies to do the conversion?
There is no native SQL Server way to perform this conversion. SQL Server knows nothing of image data and just sees those blobs as a pile of bytes.
You should do this conversion as a separate step after the rest of your conversion and use a tool appropriate for the task. That means a program or script which can query the data, perform the conversion (perhaps using a utility like ImageMagick), then update the data. An even safer option would be to create a new column for the PNG and insert the converted image there, rather than overwriting the JPEG; later, when you're satisfied that no one is using the JPEG any longer, you can drop the column from the table.

Tool/method to convert a varbinary to an image file

I have a table in a SQL Server 2008 with images (JPG) stored in a varbinary column. I was wondering if there's a really simple way of converting a varbinary back to a image file.
For example - I'm using Management Studio, and I am able to just right click on my "cell" with the data in hex format (0xFFD8FFDB0084... etc.) I can paste that sting into a text file. Is there a nice tool to execute on that text file to convert it to a binary file?
Unfortunately, i DO NOT have any EXECUTE permission on this database... (Otherwise I would have been able to use BCP.)
The most convenient method of extracting images from my database was to use a PowerShell script explained here
As mentioned by #SqlACID, simply copying the data from the column i SQL Management Studio would truncate the varbinary to 65K.

Saving text file in db and retrieving

I have to store a text file in the form of byte array and has to read it back from the database and need to write on text file. What can i Do? I am using sql server 2008 R2 and vb.net
The could use varbinary(max) for the data type in sql. If saving space change max to a smaller number better noted here: http://msdn.microsoft.com/en-us/library/ms188362.aspx
You can convert the text file to byte[] and store it in column of image datatype. When you retrieve this data from data base you will need to type cast to byte[] and using FileStream you can convert it into the file.
Following are some helpful links
http://www.aspdotnet-suresh.com/2011/01/how-to-insert-images-into-database-and.html
http://social.msdn.microsoft.com/Forums/en/netfxbcl/thread/42cec0cb-5761-4aaa-93dc-861b29ee5ea6
Hope this is what you are looking for.