blob

I am storing images in MYSQL. I have table as CREATE TABLE myTable (id INT, myImage BLOB); When I am trying to insert 4.7MB file, I am getting exception as com.mysql.jdbc.PacketTooBigException: Packet for query is too large (4996552 > 1048576). You can change this value on the server by setting the max_allowed_packet' variable. I believe this is related to image size only. Is there any other variable type that I can use? Update 1 As per older SO question, I also tried with MEDIUMBLOB but still I am getting same error. Adding Image to a database in Java Update 2 At the start of the project, I

I have a string that I called Blob() on: var mystring = "Hello World!"; var myblob = new Blob([mystring], { type: 'text/plain' }); mystring = ""; How do I get the string back out? function getBlobData(blob) { // Not sure what code to put here } alert(getBlobData(myblob)); // should alert "Hello World!" In order to extract data from a Blob, you need a FileReader . var reader = new FileReader(); reader.onload = function() { alert(reader.result); } reader.readAsText(blob); If the browser supports it, you could go via a blob URI and XMLHttpRequest it function blobToString(b) { var u, x; u = URL

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How can I tell Activerecord to not load blob columns unless explicitly asked for? There are some pretty large blobs in my legacy DB that must be excluded for 'normal' Objects. I just ran into this using rail 3. Fortunately it wasn't that difficult to solve. I set a default_scope that removed the particular columns I didn't want from the result. For example, in the model I had there was an xml text field that could be quite long that wasn't used in most views. default_scope select((column_names - ['data']).map { |column_name| "`#{table_name}`.`#{column_name}`"}) You'll see from the solution

For my client I have to use blob storage for some various files. So I have created a independent bundle with a Blob class extends Doctrine\DBAL\Types\Type. and with a boot function in the bundle class. That works pretty fine I can write in the database Blob datas. But I can't download any document after :/ I have got: public function downloadAction($id) { $em = $this->getDoctrine()->getManager(); /* @var $entity Document */ $entity = $em->getRepository('Lille3SapBundle:Document')->find($id); if (!$entity) { throw $this->createNotFoundException('Unable to find Document entity.'); } $file =

I have a database which has a number of files stored in a BLOB field. How can I extract & save the original files? There are many different file types - doc, pdf, xls, etc. The table has the extension in one col, and the original file name in another. There may be multiple files with the same file name, too. You can use the UTL_FILE package to do this in version 9i onwards something like this: DECLARE l_file UTL_FILE.FILE_TYPE; l_buffer RAW(32767); l_amount BINARY_INTEGER := 32767; l_pos NUMBER := 1; l_blob BLOB; l_blob_len NUMBER; BEGIN SELECT blobcol INTO l_blob FROM table WHERE rownum = 1;

While searching trough SO, I've found two contradicting answers (and even a comment that stated that) but no definitive answer: The problem is: is there any performance benefit, if you store a TEXT/BLOB field outside of a table? We assume: You SELECT correctly (only selection the TEXT/BLOB if required, no SELECT *) Tables are indexed properly, where it makes sense (so it's not a matter of 'if you index it') The database design doesnt really matter. This is a question to identify the MySQL behaviour in this special case, not to solve certain database design problems. Let's assume this Database