Maybe. A 'file of record' with an in-memory hash or nary-tree index will get you there in one disk access and not significantly more than 19 key comparisons. This may be a lot better than an enormous in-memory structure and the vagarities of the virtual memory system (unless of course, you pin it in memory)
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Neven MacEwan Sent: Thursday, November 01, 2001 11:00 PM To: Multiple recipients of list delphi Subject: Re: [DUG]: Dynamic Arrays V Strings Lists David Can you give more info 1/ How are you accessing the info, by position or indexed (and how many ways, and by what type of keys, string, integer etc) 2/ Is the data static or dynamic (ie can you stream the data in and then sort it or is it constantly updated) 5/ Are the records fixed length 4/ What sort lookup time are you aiming at? My gut feeling is (assuming 1 index, fixed length data) 1/ Allocate a f***ing great array of records 2/ Stream in your data using a hash function to position them in your array 3/ Lookup using a hash then linear search You are going to require a Gig of memory anyway HTH Neven ----- Original Message ----- From: "David Smith" <[EMAIL PROTECTED]> To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> Sent: Thursday, November 01, 2001 5:00 PM Subject: [DUG]: Dynamic Arrays V Strings Lists > Hi, > > Any one have ideas or experience if Dynamic arrays or string\object lists is > faster for accessing an element. > > Am developing an application where microns (maybe microseconds) for > accessing an item in a list over 500 000 items (about 1500 bytes each) based > on an index is very important. > > Thanks, > David. > --------------------------------------------------------------------------- New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] Website: http://www.delphi.org.nz To UnSub, send email to: [EMAIL PROTECTED] with body of "unsubscribe delphi" Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/ --------------------------------------------------------------------------- New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] Website: http://www.delphi.org.nz To UnSub, send email to: [EMAIL PROTECTED] with body of "unsubscribe delphi" Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
