Files
harbour-core/harbour/contrib/bmdbfcdx
Przemyslaw Czerpak d1f8cc8478 2007-05-04 15:35 UTC+0200 Przemyslaw Czerpak (druzus/at/priv.onet.pl)
* harbour/contrib/Makefile
  * harbour/contrib/bmdbfcdx/Makefile
  * harbour/source/rdd/Makefile
    ! fixed GNU make compilation

  * harbour/include/hbapifs.h
  * harbour/source/rtl/filesys.c
    + added support for DOS/Windows DENY_* flag emulation in POSIX
      systems using BSD locks. So far such emulatin was done with
      standard POSIX locks. The new emulation can be enabled by setting
      HB_USE_BSDLOCKS and disabled by HB_USE_BSDLOCKS_OFF. By default
      it's enabled in Linux and BSD* based systems.
      Please not that it BSD locks work in differ way then POSIX ones.
      They are bound with file handle and process ID not i-node and PID.
      It will allow to synchronize even single process but it will not
      work in NFS and some old BSD and Linux kernels. This synchronization
      cannot be used also between different platforms. If someone needs
      such synchronization then he should build Harbour on all platforms
      with HB_USE_BSDLOCKS_OFF and HB_USE_SHARELOCKS with valid multi
      platform lock offset

  * harbour/source/rdd/dbcmd.c
    * removed all explicit NETERR setting - now it can be set only
      by NETERR() function (executed by default errorsys)
    * changed ordListAdd()/dbSetIndex() - now they return logical value
      with information about success

  * harbour/source/rdd/wafunc.c
    * changed hb_rddOpenTable()/hb_rddCreateTable() to make dbUseArea()/
      dbCreate() more Clipper compatible - it's not exact Clipper behavior
      but I intentionally do not want to replicate some strange for me
      things, f.e. I do not know why Clipper ignores RDDNAME when it has
      only one character

  + harbour/tests/tstuse.prg
    + test code for dbUseArea()
2007-05-04 13:36:02 +00:00
..

 BMDBFCDX RDD:
 ----------------------------------------------------------------------------

 Is a DBFCDX RDD compatible with clipper 5.3, use SET OPTIMIZE ON to make a
 static bitmap filters, with SET OPTIMIZE OFF works as harbour DBFCDX.

 Addons:

     BM_DbSeekWild( uKey, [lSoftSeek], [lFindLast], [lNext], [lAll] ) => .T./.F. or aSeekRec when lAll clause
     BM_Turbo( lOnOff ) // Is only recomendable to use it on creating FILTERS
     BM_DbGetFilterArray() => aFilterRec
     BM_DbSetFilterArray( aFilterRec )
     BM_DbSetFilterArrayAdd( aFilterRec )
     BM_DbSetFilterArrayDel( aFilterRec )

 Respecting command:

 SET OPTIMIZE
 Change the setting that determines whether to optimize using the open orders
 when processing a filtered database file
------------------------------------------------------------------------------
 Syntax

     SET OPTIMIZE ON | OFF | (<lToggle>)

 Arguments

     ON enables optimization.

     OFF disables optimization.

     <lToggle> is a logical expression that must be enclosed in
     parentheses.  A value of true (.T.) is the same as ON, and a value of
     false (.F.) is the same as OFF.

     Note:  The initial default of this setting depends on the RDD.

 Description

     For RDDs that support optimization, such as DBFCDX, SET OPTIMIZE
     determines whether to optimize filters based on the orders open in the
     current work area.  If this flag is ON, the RDD will optimize the search
     for records that meet the filter condition to the fullest extent
     possible, minimizing the need to read the actual data from the database
     file.

     If this flag is OFF, the RDD will not optimize.

 Examples

     ¦  The following example enables optimization for the Inventor
        database file using the SET OPTIMIZE command:

        USE Inventor NEW VIA "DBFCDX"
        SET OPTIMIZE ON