OK, this seems really helpful, but I'm afraid you've lost me a bit. 1. Third normal??? :)
2. Your idea would be to have one table that's relatively static, with the names (and perhaps other data) of the stocks, a 2nd table that holds prices? I'm not sure I see the advantage of this approach. 3. What's "Instance DateTime?" 4. Are you saying that I could use "GROUP BY" to get daily, monthly, yearly, etc? Thanks, very helpful...just what I'm needing! > Third normal says: > > Table: Stock > ID Integer Primary Key, > Symbol Varchar(n), > ... Other stuff .... > > Table: DaylyPrice (I'd call it "Price") > StockID Integer (Foreign key: Stock:ID) > Instance DateTime > Price Integer (Price times 100/1000/10000, Your choice) > > Then you can have virtually unlimited stocks with virtually unlimited > prices. Price sampling can be done at any rate (i.e. seconds, hourly, > daily, weekly, etc.) Your queries would determine "closing price" hourly, > dally, monthly, etc. > > Thoughts to ponder: How to handle stock "splits", Mergers, and ? > > Fred > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of cstrader > Sent: Tuesday, August 19, 2008 11:53 AM > To: General Discussion of SQLite Database > Subject: Re: [sqlite] 2 Questions from a newbie > > > OK, cool idea... let me try that. > > > ----- Original Message ----- > From: "Jeff Hamilton" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]>; "General Discussion of SQLite Database" > <sqlite-users@sqlite.org> > Sent: Tuesday, August 19, 2008 12:51 PM > Subject: Re: [sqlite] 2 Questions from a newbie > > >> If all 2,400 tables have the same 9 columns you could try using a >> single table and adding a column for the ticker of the stock and then >> add an index to that column to allow quick lookups based on the >> ticker. >> >> -Jeff >> >> On Tue, Aug 19, 2008 at 9:44 AM, .:UgumugU:. <[EMAIL PROTECTED]> wrote: >>> Hi cstrader, >>> >>> Just send some table structure and the explain what you are trying todo. >>> In my opinion it is not a good way to deal with 2400 tables :) >>> >>> ugumugu >>> >>> cstrader yazm?s,: >>>> I'm just starting with SQLite (from vb.net) and could use some advice. >>>> >>>> I have a set of 2400 (could get substantially higher) tables in a >>>> single >>>> database (each table contains daily stock prices for a different >>>> stock). >>>> Each table has 9 columns (all text for now) and some several thousand >>>> rows. >>>> So far so good. >>>> >>>> I need to read those tables sequentially and operate on them. It takes >>>> about 18 seconds to open each of the tables in sequence. (i.e. loop >>>> through 2400 tables with a select command opening each one) >>>> >>>> First question... does that sound about right in terms of speed? Is >>>> there a >>>> way to store the data that might be faster? The data are primarily >>>> single >>>> precision -- I'm using text format, but perhaps that's not best? >>>> >>>> Second question: >>>> >>>> When I open each table I need to add some blank columns to it. So I >>>> include >>>> some "0 as NewCol" lines to create the new columns with initial 0s. >>>> >>>> However, adding 20 new columns in this manner increases the total time >>>> for >>>> the loop from 19 seconds to 49 seconds. This seems like a long time. >>>> Is >>>> there a faster way to get these empty columns in? >>>> >>>> More questions later I'm sure... >>>> >>>> Thanks in advance >>>> >>>> cs >>>> >>>> _______________________________________________ >>>> sqlite-users mailing list >>>> sqlite-users@sqlite.org >>>> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >>>> >>>> >>> >>> _______________________________________________ >>> sqlite-users mailing list >>> sqlite-users@sqlite.org >>> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >>> >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users@sqlite.org >> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
