Hi David, The application I have in mind is for images. In my case, size of images is known and they are not big. As an example, a 64*32 image will have 2048 pixels. If they are 8-bit grey-level pixels, the image occupies 2KB memory.
I may venture to guess that the unknown size and type of a blob object in MySQL prevent it from being very usable in R since R doesn't have a datatype for a binary blob? Thanks! Jonathan -----Original Message----- From: David James [mailto:[EMAIL PROTECTED] Sent: Wednesday, September 22, 2004 7:05 AM To: LI,JONATHAN (A-Labs,ex1) Cc: [EMAIL PROTECTED] Subject: Re: [R] RMySQL and Blob Hi Jonathan, Currently RMySQL doesn't handle blob objects. The mechanics of inserting and extracting blob objects by itself is not too hard, but issues such as how should blobs be made available to R, how to prevent buffers overflows, how to prevent huge blobs from exhausting the available memory, should R callback functions be invoked as chunks of the blob are brought in, etc., need more consideration. And these issues are not R/MySQL specific, but also relevant to other databases and other non-dbms interfaces. BTW there are R facilities (e.g., external pointers, finalizers) that seems quite important for this type of implementation. What type and how big are the blobs that want to import? -- David [EMAIL PROTECTED] wrote: > Dear R experts, > > Does RMySQL package handle Blob datatype in a MySQL database? Blob can represent an > image, a sound or some other > large and complex binary objects. In an article published by R-database special > interest group, named "A common database interface (DBI)" (updated June 2003), it's > mentioned in "open issues and limitations" that "We need to carefully plan how to > deal with binary objects". > > Before I invest time to try, I would appreciate any experts' opinions. > > Thanks, > Jonathan > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
