[firebird-support] Why when i create a Primary Key that is also a foreign key 2 index are created ?
Hello, Why when i create a Primary Key that is also a foreign key 2 index are created ? or i make a mistake somewhere ?
[firebird-support] Re: Table where we add 2 000 000 rows everydays and delete them every night
You could use a sequence/generator for that without multi user problems and very fast. not really (but the idea is good), because i need also field like NB_database_update_by_user ... :( and in this way i will need to create as much sequence/generator than i have users (thousands of thousands) :(
Re: [firebird-support] Why when i create a Primary Key that is also a foreign key 2 index are created ?
-- Original Message --- From: nathanelrick nathanelr...@yahoo.fr Why when i create a Primary Key that is also a foreign key 2 index are created ? or i make a mistake somewhere ? --- End of Original Message --- http://www.firebirdsql.org/refdocs/langrefupd20-create-table.html#langrefupd20-ct- using-index (see blue and red notes) Correct. You cannot share an index between multiple index-using constraints, they each get their own. If you were to drop the primary key constraint, and the foreign key were re-using the primary key's unique index, you'd have a problem: the foreign key would need a non-unique index after the drop, or it would accidentally still be a unique foreign key [physical] even though no remaining constraint [logical] required it to be. Going the other way, you'd have a primary key using a slight-less-efficient non- unique index created by the foreign key, and it couldn't rely on the index itself to magically enforce the uniqueness of the primary key. The two concepts get tied together internally, such that using a unique index [physical] enforces the constraint [logical] -- AFAIK Firebird can't enforce a PK without a unique index, it doesn't have a backup mechanism that can use non-unique indices nor do a full-table-scan/sort/count... While reference-counting might help in the few situations where multiple indexed constraints could share indices, I think the use cases for that are rather rare. Two unique constraints on the same field, or sharing the first few fields of their definition? Two foreign keys sharing one or several fields? (One being a superset of the other.) ... Pretty rare. -Philip
[firebird-support] Firebird 1.5: How to tell the size of one table inside Fdb file?
Hi to all, I have a Firebird 1.5 database that has grown up to 26.6 Gb. Most of the data is stored in one single table that holds a memo field. I'm worried about the size of this table, because as far as I know the maximun table size for version 1.5 is about 36 Gb and I guess I'll soon get close to this limit. How can I tell the size of a single table inside the Fdb file. Thank your for any help. Nando.
Re: [firebird-support] Firebird 1.5: How to tell the size of one table inside Fdb file?
Em 14/2/2012 22:46, Nando escreveu: Hi to all, I have a Firebird 1.5 database that has grown up to 26.6 Gb. Most of the data is stored in one single table that holds a memo field. I'm worried about the size of this table, because as far as I know the maximun table size for version 1.5 is about 36 Gb and I guess I'll soon get close to this limit. How can I tell the size of a single table inside the Fdb file. Thank your for any help. Nando. Look on the gstat output for the number of data pages and multiply it by your page size. see you !
RE: [firebird-support] Firebird 1.5: How to tell the size of one table inside Fdb file?
I have a Firebird 1.5 database that has grown up to 26.6 Gb. Most of the data is stored in one single table that holds a memo field. I'm worried about the size of this table, because as far as I know the maximun table size for version 1.5 is about 36 Gb and I guess I'll soon get close to this limit. I am 99.9% sure that the limit applies to data not counting blobs. How many rows are in the table? Sean
Re: [firebird-support] Firebird 1.5: How to tell the size of one table inside Fdb file?
Sean, I am 99.9% sure that the limit applies to data not counting blobs. The limit on table size does not include the actual size of blobs, but considers each blob to be eight bytes long. Advance yourself to 100% confident. Cheers, Ann
[firebird-support] what the most efficient way to do update or insert with value ?
hello, i want to do something like update or insert into mytable(ID, amount) values (123, amount + 100); how to do this ?
Re: [firebird-support] what the most efficient way to do update or insert with value ?
Em 15/2/2012 04:54, nathanelrick escreveu: hello, i want to do something like update or insert into mytable(ID, amount) values (123, amount + 100); how to do this ? :) Pretty hard to answer anything taking into account the information you provided
