Alter index to cluster & blob

Hello, I would like to know the behaviour of the syntax "alter index to cluster" useful to defragment the extents of a table, if I have great blob objects in my tables. These blob remain into the databaes, or are 'exported' from the alter command? Thank you, Francesco

checco_vero@libero.it wrote: > Hello, > > I would like to know the behaviour of the syntax "alter index to > cluster" useful to defragment the extents of a table, if I have great > blob objects in my tables. These blob remain into the databaes, or are > 'exported' from the alter command? > Using ALTER INDEX ... TO CLUSTER doesn't export anything. It sorts the data portion of a table by the index's key and rewrites the table into a new set of extents in sorted order. Since dumb BLOB pages, even IN TABLE blob pages are not contained on the row's core data pages but on separate BLOB pages either in BLOB space or table space and smart BLOB (or SLOB) pages are separately contained in SmartBlob spaces, they are not equally affected. Tablespace dumb BLOBs can take up part of a page which it will share with other small BLOB columns from other rows or one or more full BLOB pages plus some remainder segment which shares space. The in-table blob pages will be reorged into new extents as well, but not strictly sorted with the table's non-special column data. Blobspace blob pages (dumb or smart) are completely unaffected by such a reorg. Art S. Kagel Oninit > Thank you, > Francesco =========================================================================================== Please access the attached hyperlink for an important electronic communications disclaimer: http://www.oninit.com/home/disclaimer.php ===========================================================================================