Re: Calculating BLOB space table size

Steve N. wrote: [snip] > Maximum row size 86 > Number of special columns 1 > Number of keys 0 > Number of extents 155 > Current serial value 1 > First extent size 8 > Next extent size 4096 You don't tell what IDS version and platform, but there's a limit on the number of extents per table. If your system is using 2 GB pages the limit is a little more than 200 extents. You have 155 now!

Claus Samuelsen <csa@eye-bee-em.com> wrote in message news:<41494a91$0$204$14726298@news.sunsite.dk>... > > You don't tell what IDS version and platform, but there's a limit on the > number of extents per table. If your system is using 2 GB pages the > limit is a little more than 200 extents. You have 155 now! Thanks, Claus. We are using IDS 9.30.UC2 with (I believe) the default page size (buffer size = 4096). Since these images will be kept for 5-7 years, I will certainly check into that limitation. Thx Steve

Steve N. wrote: > > We are using IDS 9.30.UC2 with (I believe) the default page size > (buffer size = 4096). Since these images will be kept for 5-7 years, I > will certainly check into that limitation. > With a 4 KB page size you'll be safe for a while. If you're going to reorganize your table to reduce the number of extents, you should consider placing the blobs in a blobspace. With a blobspace you can decide a blobspace page size that's suitable for the blobs. From the oncheck output your average blob size is about 50 kb. If you want more info you can do a "select min(length(data)), avg(length(data)), max(length(data)) from image_rec". Be careful when deciding the blobspace page size as there's no remainder page in blobspaces. If you have a blobspace page size of 48 kb and store a 49 kb blob you'll have 47 kb unused! From the fine manual: When you store simple large objects in a blobspace on a separate disk from the table with which it is associated, the database server provides the following performance advantages: 1) You have parallel access to the table and simple large objects. 2) Unlike simple large objects stored in a dbspace, blobspace data is written directly to disk. Simple large objects do not pass through resident shared memory, which leaves memory pages free for other uses. 3) Simple large objects are not logged, which reduces logging I/O activity for logged databases. Also consider upgrade to IDS 9.40. You'll probably not be able to dbexport the database as the unload file for image_rec table will pass the 2 GB limit (it can still be done with the manual unload command using fitting intervals).