Re: dynamic object creation
От | Mark Volpe |
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Тема | Re: dynamic object creation |
Дата | |
Msg-id | 39E5C914.F764BA47@epamail.epa.gov обсуждение исходный текст |
Ответ на | dynamic object creation (Indraneel Majumdar <indraneel@www.cdfd.org.in>) |
Ответы |
Re: dynamic object creation
(Indraneel Majumdar <indraneel@www.cdfd.org.in>)
|
Список | pgsql-sql |
You may want to think about creating your table like this (for example): CREATE TABLE data (key text,field_type char,value text ); CREATE UNIQUE INDEX data_key ON data(key, field_type, value); So this way each "record" takes up several rows in the table, and each "field" can take up as many rows as you need. A table like this, with two columns being arrays: key | field1 | field2 ------------------------- a | [x,y,z] | [a,d,f] b | [m,n] | (NULL) Can be represented like this instead: key | field_type | value ------------------------- a | 1 | x a | 1 | y a | 1 | z a | 2 | a a | 2 | d a | 2 | f b | 1 | m b | 1 | n I'm not sure what your data looks like, but I hope this helps. Mark Indraneel Majumdar wrote: > > Hi, > > I'm not sure if the subject line has been proper. I have this following > problem which I hope PostgreSQL can handle. > > I'm converting a complex flatfile where records are arranged serially. > some fields are as 'n' times repeating blocks of multiple lines. Some > subfields within these are also 'n' time repeating blocks of multiple > lines. So in my main table I do not know (until at run time) how many > fields to create (same for any sub tables). How can I do this dynamically? > > I tried using arrays, but retrieval from that is causing some problems. I > have already checked the array utilities in the contrib section and have > extended the operator list for other types (I'll send the file to it's > original author so that he may include it if he wishes). > > I think there must be some object-oriented way of doing this without > creating too many keys. or are keys the only and best method? Using this > is causing a performance hit. If it's any help, what I'm trying to convert > are biological databases distributed in 'SRS' flatfile format from > ftp.ebi.ac.uk/pub/databases/ > > Thank you, > Indraneel > > /************************************************************************. > # Indraneel Majumdar ¡ E-mail: indraneel@123india.com # > # Bioinformatics Unit (EMBNET node), ¡ URL: http://scorpius.iwarp.com # > # Centre for DNA Fingerprinting and Diagnostics, # > # Hyderabad, India - 500076 # > `************************************************************************/
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