Re: [firebird-support] Re: What is the optimum pageSize?
On 2019-11-14 23:47, blackfalconsoftw...@outlook.com [firebird-support] wrote: > Doesn't the page size definition as per a database depend on one > designs their database tables and how such tables will be used? The page size doesn't restrict or limit your database design, with the exception of indexable items. The maximum keysize is slightly less than 1/4 of the page size. This means that with a page size of 4096, the max you can index is +/- VARCHAR(1020) in a single byte character set or +/- VARCHAR(256) UTF8 (I'm saying +/- here because exact size depends on collations etc), while with page size 16384, the maximum is +/- VARCHAR(4092) single byte character set / VARCHAR(1023) UTF8. That said, trying to avoid such oversized indexes would be better: the more keys fit on a single page, the more efficient the index. With a larger page size, more records will fit on a single page (or very wide records might fit on less pages). Page size can have influence on performance, and generally larger page sizes are 'better' (although that also depends on the underlying storage). However, if you use a lot of relatively small blobs, you could be wasting more diskspace. Mark
Re: [firebird-support] Re: What is the optimum pageSize?
On 2019-11-15 00:12, Clyde Eisenbeis cte...@gmail.com [firebird-support] wrote: > Thanks for clarifying! This is very useful info, especially the > ibexpert.net [1] site. > > Is there a Firebird site that provides details such as CHAR and > VARCHAR max sizes, pageSize size options, etc.? Most of it is described in the Firebird 2.5 Language Reference: https://firebirdsql.org/file/documentation/reference_manuals/fblangref25-en/html/fblangref25.html Datatype sizes: https://firebirdsql.org/file/documentation/reference_manuals/fblangref25-en/html/fblangref25-datatypes.html Page sizes: https://firebirdsql.org/file/documentation/reference_manuals/fblangref25-en/html/fblangref25-ddl-db.html If you're using Firebird 3, also consult the Firebird 3 release notes for things introduce or changed: https://firebirdsql.org/file/documentation/release_notes/html/en/3_0/rlsnotes30.html Mark
Re: [firebird-support] Re: What is the optimum pageSize?
Thanks for clarifying! This is very useful info, especially the ibexpert.net site. Is there a Firebird site that provides details such as CHAR and VARCHAR max sizes, pageSize size options, etc.? ``` On Thu, Nov 14, 2019 at 5:07 PM Dimitry Sibiryakov s...@ibphoenix.com [firebird-support] wrote: > 14.11.2019 23:47, blackfalconsoftw...@outlook.com [firebird-support] > wrote: > > Doesn't the page size definition as per a database depend on one designs > their database > > tables and how such tables will be used? > >Cases when pages of smaller size have a speed advantage are very > special and most of > database developers won't ever hit them. In common case small pages cause > slowdown. > > > -- >WBR, SD. > > > > > > > ++ > > Visit http://www.firebirdsql.org and click the Documentation item > on the main (top) menu. Try FAQ and other links from the left-side menu > there. > > Also search the knowledgebases at > http://www.ibphoenix.com/resources/documents/ > > ++ > > > Yahoo Groups Links > > > >
Re: [firebird-support] Re: What is the optimum pageSize?
14.11.2019 23:47, blackfalconsoftw...@outlook.com [firebird-support] wrote: > Doesn't the page size definition as per a database depend on one designs > their database > tables and how such tables will be used? Cases when pages of smaller size have a speed advantage are very special and most of database developers won't ever hit them. In common case small pages cause slowdown. -- WBR, SD. ++ Visit http://www.firebirdsql.org and click the Documentation item on the main (top) menu. Try FAQ and other links from the left-side menu there. Also search the knowledgebases at http://www.ibphoenix.com/resources/documents/ ++ Yahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/firebird-support/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/firebird-support/join (Yahoo! ID required) <*> To change settings via email: firebird-support-dig...@yahoogroups.com firebird-support-fullfeatu...@yahoogroups.com <*> To unsubscribe from this group, send an email to: firebird-support-unsubscr...@yahoogroups.com <*> Your use of Yahoo Groups is subject to: https://info.yahoo.com/legal/us/yahoo/utos/terms/
