[Rd] RSQLite indexing
seth at userprimary.net
Tue Oct 23 06:33:07 CEST 2007
Jeffrey Horner <jeff.horner at vanderbilt.edu> writes:
> Thomas Lumley wrote on 10/22/2007 04:54 PM:
>> I am trying to use RSQLite for storing data and I need to create indexes on
>> two variables in the table. It appears from searching the web that the CREATE
>> INDEX operation in SQLite is relatively slow for large files, and this has been
>> my experience as well.
What is your schema? In particular, are things that are integers or
floats being stored that way in SQLite?
I believe the annotation data packages via AnnotationDbi are using
cache_size=64000 and synchronous=0 and that this was determined by a
handful of experiments on typical annotation dbs.
Columns with few levels may not benefit from an index. See this
But your column with many levels should suffer this problem :-)
Seth Falcon | seth at userprimary.net | blog: http://userprimary.net/user/
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