Subject | Re: [Firebird-general] New Open Source DBMS evaluation document available |
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Author | Ann W. Harrison |
Post date | 2005-06-13T17:14:42Z |
marius popa wrote:
The next most important is that the db_key is 32 bits and db_keys are
not dense, so a table with somewhere between 40 and 70 Gb of data, runs
out of db_keys. Both of those are fixed in FB2 - index keys up to 1/4
of a database page and 40 bit db-keys. Note, though, that neither of
those is "unlimited". And do remember that our page numbers are also 32
bits, so the largest possible database has 4Gb of 16Kb pages... that's
big, but not "unlimited".
databases that say they support an unlimited number of records and
figure out what they use for a record identifiers.
extend Firebird database sizes. The Vulcan changes are in other areas.
Cheers,
Ann
> from the paper i see firebird 1.5.2 still have some limitsThe major limit in Firebird 1.5.2 is the the length of the index key.
The next most important is that the db_key is 32 bits and db_keys are
not dense, so a table with somewhere between 40 and 70 Gb of data, runs
out of db_keys. Both of those are fixed in FB2 - index keys up to 1/4
of a database page and 40 bit db-keys. Note, though, that neither of
those is "unlimited". And do remember that our page numbers are also 32
bits, so the largest possible database has 4Gb of 16Kb pages... that's
big, but not "unlimited".
>Nothing is unlimited, and if it were up to me, I'd go back to the
> if we want to use it with very large databases :
> unlimited table number, unlimited size ... etc
databases that say they support an unlimited number of records and
figure out what they use for a record identifiers.
> I will try to see what are limits with fb2.0 or vulcanAs far as I can remember, indexes and db_keys are the two changes that
extend Firebird database sizes. The Vulcan changes are in other areas.
Cheers,
Ann
>