Posts: 1091

Joined: Thu Nov 17, 2005 11:08 AM

Field name length
Posted: Wed Oct 07, 2009 08:14 AM

Hi everybody,
does exist a function that convert long field name (for instance helpful in a import program from Sql to Dbf).
into a dbf compatibile field_name (max 10 char)?

Any hints?

Does exist a kind of dbf file type that permits FIELD_NAME lenght > 10 char?

It would be nice to create a new DBF format which allows to go beyond this limit.

Thanks in advance
marco

Marco Boschi
info@marcoboschi.it

Antonio Linares

Posts: 44158

Joined: Thu Oct 06, 2005 05:47 PM

Re: Field name length
Posted: Wed Oct 07, 2009 11:55 PM

Marco,

If you use FWH Class TDataBase then you could easily "translate" long fieldnames into shortfield names in a similar way as Windows generates short filenames from long filenames.

This is an example to review the way Windows does it:

Code (fw): Select all Collapse

function Main()

   lMkDir( "This is a long fieldname 1" )
   lMkDir( "This is a long fieldname 2" )

   MsgInfo( LFN2SFN( "This is a long fieldname 1" ) )
   MsgInfo( LFN2SFN( "This is a long fieldname 2" ) )
   
return nil

You could create a function to make a similar conversion. Once you have it, then you could inherit from FWH Class TDataBase or modify it, so when a long fieldname is used, the TDataBase object translates it into its equivalent short fieldname:

MsgInfo( oDbf:ALongFieldName ) // the object class will translate it into a search for "ALONG~1", etc

To improve the search speed you could use hashes:

Code (fw): Select all Collapse

function Main()

   local hValue := {=>}

   hValue[ "LONGFIELDNAME1" ] := "LONGF~1"
   hValue[ "LONGFIELDNAME2" ] := "LONGF~2"

   MsgInfo( hValue[ "LONGFIELDNAME1" ] )
   MsgInfo( hValue[ "LONGFIELDNAME2" ] )
   
return nil

regards, saludos

Antonio Linares
www.fivetechsoft.com

MarcoBoschi

Posts: 1091

Joined: Thu Nov 17, 2005 11:08 AM

Re: Field name length
Posted: Thu Oct 08, 2009 06:50 AM

Antonio,
many thanks now do a test and then you'll know if it works.

Marco

Marco Boschi
info@marcoboschi.it

MarcoBoschi

Posts: 1091

Joined: Thu Nov 17, 2005 11:08 AM

Re: Field name length
Posted: Thu Oct 08, 2009 07:16 AM