OpenEuphoria

Re: Databases and Keys

• Posted by irvm at ellijay.com Dec 10, 2001
• 403 views

On Monday 10 December 2001 05:42 am, you wrote:

> Hi All,
> I'm currently writting my own Music DB and wondered how other go about
> generating a record key. I thought about using the song title but no good
> because mor than one song may have the same name, so I considered joining
> the song name and the artist but again no good as the same song may be on a
> couple od CD's. The only othe thing I can think of is using date() as the
> key but it seems like a real waste and searching the db for a song title
> etc. would become slow. Alternativly how can I build many indexes.

You could use the UPC, it would be a unique identifier. (see note below)
As for locating things quickly, it's pretty easy to create your own indexes; 
perhaps Junko's hash routines will help. Since the indexes only have to be 
updated when a  new CD is added to the collection, speed is not an issue. 
Indexing 5,000 records takes about 1 sec. on my pc.

Schema for main table;
KEY = UPC
DATA = {ALBUM TITLE, ARTIST, { TRACK1, TRACK2, TRACK3.....} }

Indexes are stored in tables:
   ARTIST , key is artist name
       Howlin' Wolf , { 76732590829 } 
                           -- have 1 album by Howlin' Wolf
       Stevie Ray Vaughn , {774646587027, 44744906938, ...}
                           -- have two by Stevie Ray

    TITLE , key is album name
        Texas Flood, { 74646587027, 453534555 } 
                            -- 2 albums have that name
        Pride & Joy, { 44744906938 }
    
    TRACK , key is song title:
       Tell Me, {  74646587027 , 76732590829 } 
                    -- done by Howlin' Wolf and Stevie Ray
       Testify, { 7464387342 } 
                   -- only one cd has a track by that name
        
Note: I just noticed that albums purchased in Mexico have no UPC.... I guess 
you could look them up on the web, or just assign a random number.

Regards,
Irv