Space required for partition by growth table space
Notations used to calculate space for a partition-by-growth table space
Notation | Description |
|---|---|
mbytes | 1048576 MB |
Headerpage | If segsize=0 then Headerpage =1, otherwise, Headerpage=0 |
Dictionary pages | Dictionary pages if a compressed table space |
FLOOR | The operation of discarding the decimal portion of the real number |
mpages | Data pages for each space map. If segsize=0, mpages - 1 |
rpp | Rows per page |
Total rows | Total number of rows |
DsSize | Data set size |
PgSize | Page size |
segsize | Segment size |
Total number of pages in a partition by growth table space
The formulas in the following table are approximations.
Total number of pages in a partition-by-growth table space
Value | Formula |
|---|---|
Total pages for a full partition | TPagesPart=(dssize/mbytes)*(mbytes/PgSize) |
Space map pages for a full partition | SmapsPart = FLOOR(TPagesPart-dictionary pages - 1)/mpages + 1 |
Remove overhead pages to get data pages for a full partition | DPagesPart= TPagesPart-(SmapsPart+headerpage+dictionary pages +1) |
Adjust data pages for segsize if table space is segmented | ADPagesPart= DpagesPart-(segsize*(FLOOR(((DPagesPart + segsize -1)/segsize)) +1) - DPagesPart) |
Remove freepages from data pages for total pages that can have data in a partition | FullPagesPart=DPagesPart-FLOOR((DPagesPart/freepages+1)) |
Full partitions used after freepage removed | FullParts=FLOOR(TotalRows/(rpp*FullPagesPart)) |
Remaining rows for last partition (if any) | RmainRows=TotalRows-(rpp*FullPagesPart*FullParts) |
Data pages in last partition used (if any) | LastDPagesPart=FLOOR(RmainsRows/rpp)+dictpages+1 |
Space map pages for last partition (if any) | LastTPSmapsPart=FLOOR(((LastDPagesPart+headerpage)+(mpages-1))/mpages) |
Freepages in last partition used (if any) | LastFPagesPart = LastDPagesPart/freepage |
Total Pages in last partition used (if any) | LastTPagesPart=LastDPagesPart+LastFPagesPart+LastTPSmapsPart |
Total Pages in tablespace | TTsPages=(TPagesPart*FullParts)+ LastTPagesPart |