Reading BLOB data from Oracle database using python - oracle

This is not a question of a code, I need to extract some BLOB data from an Oracle database using python script. My question is what are the steps in dealing with BLOB data and how to read as images, videos and text? Since I have no access to the database itself, is it possible to know the type of BLOBs stored if it is pictures, videos or texts? Do I need encoding or decoding in order to tranfer these BLOBs into .jpg, .avi or .txt files ? These are very basic questions but I am new to programming so need some help to find a starting point :)

If you have a pure BLOB in the database, as opposed to, say, an ORDImage that happens to be stored in a BLOB under the covers, the BLOB itself has no idea what sort of binary data it contains. Normally, when the table was designed, a column would be added that would store the data type and/or the file name.

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Oracle small blob vs large blob

I would like to know what is better way of handling large files such as 3-4 gigabytes as Oracle blob SecureFile.
The scenario here is, I am planning to upload large files to oracle db over wcf service. I am spiltting file in to smaller chunks of 200mb and uploading it one by one. On oracle side, I just append to the single blob until whole files get uploaded. This happens in sequential manner. However, I am thinking to upload chunks in parallel so I can speed up the operation of uploading. But this will not possible to handle at Oracle end as I can't update single blob with multiple uploads as it would then write bytes not in the order it receives from the service. Is it good than to insert each blob separately and merge them later once into a single blob record in Oracle side?
Thanks
Jay

Difference between Database and File Storage in Parse.com

Based on the FAQ at Parse.com:
What is the difference between database storage and file storage?
Database storage refers to data stored as Parse Objects, which are
limited to 128 KB in size. File storage refers to static assets that
are stored using the Parse File APIs, typically images, documents, and
other types of binary data.
Just want some clarification here:
So the Strings, Arrays etc created are considered as Parse Objects and would fall under the database storage, also the URL of the file will be considered under the database storage since it is a Parse Object. But the actual files itself are considered under File Storage?
Thanks.
Yes. Any file that you upload to Parse goes to the File storage, the rest is stored in the database including the URL of such files.

Mass Export of BLOB data to CSV

I am working with an older Oracle database, I don't know which version of oracle, sorry, and I need to do a mass export of 200,000+ files worth of HTML data stored in BLOBs. I have downloaded and used both Toad and SQLDeveloper (Oracle's own DB GUI tool) and at best I am able to properly extract the HTML for a single row at a time.
Is there a way (query, tool, other GUI, etc...) that I can reliably do a mass export of all the BLOB data on this table to a CSV format?
Thank You.
You can use utl_file built-in package through this you can write blob data to a file.
Refer here.
I found this tool.
It works incredibly well for extracting content of any type out of any sort of LOB to a file type (HTML in this case). Takes about an hour to do 200,000 records though

SSRS - Unzip image varbinary(max) data and display

I'm working with a database-driven application that allows users to upload images which are then zipped and embedded into a database in a varbinary(max) format. I am now trying to get that image to display within an SSRS report (using BI 2005).
How can I convert the file data (which is 65,438 characters long when zipped and 65,535 characters when not zipped) into a normal varbinary format that I can then display in SSRS?
Many thanks in advance!
You'll have to embed a reference to a dll in your project and use a function to decompress the data within SSRS, see for example SharpZipLib. Consider storing the data uncompressed if possible, as the CPU / space trade off is unlikely to be in your favour here, as impage data is likely to have a poor compression ratio (it is usually already compressed).

Move Tablestorage to BlobStorage

is there any way of moving a table from the Tablestorage into the Blob Storage?
I thought of writing each line into a csv file. But is that really the fastest way?
Cheers,
Joe
The only supported way would be to download the data from Azure Table through Query Entities locally, then write back the data in any form you need against Blob Storage; that could be CSV, some binary format, JSON, etc..
Azure Storage does not provide any Copy or backup functionality from AzureTable to AzureBlob. It is an already requested feature but we don't have any timeline to share.
Thanks,
Jean

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