If you are fetching fixed width fields (not VARCHAR VARBINARY ) or other variable length types use ddfch. It is much faster when your data is all fixed width.
On 3/14/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
Hi everybody , I'm a J newbie and I' m really amazed by its mathematical attitudes, so I started using it to analyze data from some databases using odbc extraction code like: ch=: ddcon 'dsn=firebird_pivot;uid=SYSDBA;pwd=masterkey' sh =. 'select * from PIVOT_VENDITE_SUM' ddsel ch r=. ddfet sh,_1 r2=. ddfch sh, _1 ... I've found that: a) with Firebird database engine ddfet is very slow and causes J to stop working if the number of records I read is too great (over 5000). b) with Firebird ddfch hasn't got such problem but fields seem broken (for example in a column which contains 2005 2006 2007 2008 .... the query gives 2002 0020 0720 ... Does it depends by using varchar fields ? c) with Mysql or Oracle ddfet doesn't seem to have the above problems, but queries are very slow if compared (for example) to the same queries executed with perl-dbi (dbd-odbc) Is there anybody who can suggest me anything ? Best regards Alessio Costantini Naviga e telefona senza limiti con Tiscali Scopri le promozioni Tiscali adsl: navighi e telefoni senza canone Telecom http://abbonati.tiscali.it/adsl/ ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
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