Subject | Re: [Firebird-Architect] Table structure in Firebird? |
---|---|
Author | Ann W. Harrison |
Post date | 2005-02-28T15:18:36Z |
Thomas Steinmaurer wrote:
types in the same file. Each data page contains data from only one
table. Data is compressed before being stored. The lowest level index
pages contain compressed keys and record pointers.
The problems with storing data in an index are
1) Works only for one index. Access through secondary indexes is
markedly slower
2) Broadens & thus deepens the index, reducing cache efficiency.
3) Storing a record often requires splitting and rebuilding a low level
index page. Firebird records are stored wherever space is available
4) Complicates and probably eliminates the ability to compress back
records if the key has changed.
The advantage is that it sounds really clever to sophomore computer
science students.
Regards,
Ann
Opinions in this piece, like all others, are those of the writer
>Not in the index? Firebird stores data and indexes on different pages
> other DBMS vendors explicitly state that they are using e.g. a B-tree
> like data structure for table storage. Is there a single term for
> describing what data structure is used for storing a table in a Firebird
> database?
types in the same file. Each data page contains data from only one
table. Data is compressed before being stored. The lowest level index
pages contain compressed keys and record pointers.
The problems with storing data in an index are
1) Works only for one index. Access through secondary indexes is
markedly slower
2) Broadens & thus deepens the index, reducing cache efficiency.
3) Storing a record often requires splitting and rebuilding a low level
index page. Firebird records are stored wherever space is available
4) Complicates and probably eliminates the ability to compress back
records if the key has changed.
The advantage is that it sounds really clever to sophomore computer
science students.
Regards,
Ann
Opinions in this piece, like all others, are those of the writer