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Fragment by partition

Posted in 2007

Topics: Storage & Space Management

mohitanchlia@gmail.com — — source: Usenet: comp.databases.informix

Version: Informix 10 I have couple of questions regarding fragment by partition in same dbspace: 1. Is there any limitation as to how many partition a dbspace can have. 2. Is partition name unique to dbspace or unique to index/table. Logically it should be unique to dbspace as each partition is a separate tablespace - correct me if I am wrong.

↪ replying to mohitanchlia@gmail.com
Fernando Nunes — — source: Usenet: comp.databases.informix

mohitanchlia@gmail.com wrote: > Version: Informix 10 > > I have couple of questions regarding fragment by partition in same > dbspace: > > 1. Is there any limitation as to how many partition a dbspace can > have. > 2. Is partition name unique to dbspace or unique to index/table. > Logically it should be unique to dbspace as each partition is a > separate tablespace - correct me if I am wrong. > 1. I really don't know... Couldn't find anything in the docs... Not even maximum fragments for a table... 2. Interesting. I'd say the opposite from you: The name has to be unique, because it acts as an identifier... But the docs state (SQL Syntax): "You can store fragments of the same table in multiple partitions of the same dbspace, but each name that you declare after the PARTITION keyword must be unique among partitions of that dbspace. The PARTITION keyword is required when you store more than one fragment of the table in the same dbspace. You can also use the PARTITION keyword to declare a more meaningful name for a dbspace that has only one partition." So, apparently you were right... But when I checked the ALTER FRAGMENT syntax there was no way to specify a pair "part name"/"dbspace"... So I tried: create table test_frag ( col1 integer ) fragment by expression partition p1 ( mod(col1,2) = 0) in rootdbs,partition p1 ( mod(col1,2) = 1) in dbs1; # ^ # 858: Cannot specify the same partition/space name twice in a fragmentation # specification. # # # So, the name has to be unique for the table, which I think makes sense, and the manual needs a correction... Regards. -- Fernando Nunes Portugal http://informix-technology.blogspot.com My email works... but I don't check it frequently...

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