Seagate ST43401N/ND Guida di Installazione Pagina 58

  • Scaricare
  • Aggiungi ai miei manuali
  • Stampa
  • Pagina
    / 146
  • Indice
  • SEGNALIBRI
  • Valutato. / 5. Basato su recensioni clienti
Vedere la pagina 57
If Your Version is 11.5 or 11.9.x
50
indid 2
scan selectivity 0.983249, filter selectivity 0.983249
590512 rows, 45991 pages, index height 2,
Data Row Cluster Ratio 1.000000,
Index Page Cluster Ratio 0.998609,
Data Page Cluster Ratio 1.000000
The best qualifying index is ’lineitem_pskey’ (indid 4)
costing 35 pages, with an estimate of 31 rows to be
returned per scan of the table, using no index prefetch
(size 2K I/O) on leaf pages, in index cache ’default
data cache’ (cacheid 0) with LRU replacement using no
data prefetch (size 2K I/O), in data cache ’default data
cache’ (cacheid 0) with LRU replacement
Search argument selectivity is 0.000051.
*******************************
See the Performance and Tuning Guide at
http://manuals.sybase.com:80/onlinebooks/group-
as/asg1200e/aseperf/@Generic__BookView
for information on reading trace
flag 302 output.
If Your Version is 11.5 or 11.9.x
This section covers the following topics:
•ANSI Joins
dsync Function
12.0 Query Processing Changes
ANSI Joins
ASE now supports ANSI joins. Sybase recommends that you rewrite
applications to use ANSI outer joins because they specify unambiguously
whether the
on or where clause contains the predicate. Transact-SQL syntax in
previous releases was ambiguous in some cases.
ANSI syntax allows you to write either of these types of joins:
Vedere la pagina 57
1 2 ... 53 54 55 56 57 58 59 60 61 62 63 ... 145 146

Commenti su questo manuale

Nessun commento