TabNeedPack( )

TabNeedPack()

Purpose

Finds if a table needs packing

*Author*	*Date of code (original)*	*Updated on*	*Date of page (original)*	*Updated on*
Jacques Paris jakes.paris@sympatico.ca	11Feb2001		18Feb2001

Restrictions on use

This module is distributed under the terms of the Lesser GNU General Public License. Restrictions on the use of this work in a commercial application or derivative work is described in the Lesser GNU General Public License page at: http://www.fsf.org/copyleft/lesser.html

Description

Uses the total number of rows, the number of rows containing tabular data and the number of objects (mappable tables) of an open table to find if it requires packing. Reports the findings in clear terms including if there are records without object in a mappable table. Works on mappable and tabular only tables.

External resources

Declare statement of sub_function. Include in your program. Copy/Paste if needed.

declare function TabNeedPack (
tabname as string 'name of an open table
) as smallint

Returned value(s) (function only)

   0   trouble with tabname
   1   no packing required
   2   some records are without object
   3   some records have been deleted
   4   both 2 and 3

Other required declare statement(s). Include in your program. Copy/Paste if needed.

MapBasic Code. Copy/Paste if needed.

include "mapbasic.def"

function TabNeedPack(tabname as string) as smallint

dim ir as smallint
dim nr,nt,no as integer
dim mapp as logical
onerror goto erro

mapp= TableInfo(tabname,TAB_INFO_MAPPABLE)
nr=tableinfo(tabname,TAB_INFO_NROWS)
select * from tabname where val(str$(col1))>=0
nt=selectioninfo(SEL_INFO_NROWS)
if mapp then
   select * from tabname where obj
   no=selectioninfo(SEL_INFO_NROWS)
end if
run menu command 304

if nr=nt then
   ir=1
   if mapp and nt>no then
      ir=ir+1
   end if
  else
     ir=3
     if mapp and nt>no then
        ir=ir+1
     end if
end if

tabneedpack=ir

' start optional segment
' printing within the function allows printing the numbers of records involved
do case ir
   case 1
   note tabname + " does not require packing"
      case 2
     note tabname + " contains "+str$(nt-no)+" records without object"
     case 3
     note tabname + " requires packing (there are "+str$(nr-nt)+" deleted records)"
     case 4
     note tabname + " requires packing (there are "+str$(nr-nt)+" deleted records)"
     + chr$(10)+ " and contains "+str$(nt-no)+" records without object"
end case
' end optional segment

exit function

erro:
tabneedpack=0

end function

Availability for download

Tables.zip

Example

include "mapbasic.def"
declare sub main
declare function TabNeedPack(tabname as string) as smallint
declare function SelOpenTab(byval mappabl as logical) as string
'=====================================================

sub main

dim nametab as string
dim result as smallint
dim mapp as logical

mapp=ask("Select only among mappable tables?","Yes","No")

nametab=SelOpenTab(mapp)
if nametab="" then exit sub end if

result=TabNeedPack(nametab)

do case result
   case 1
   note nametab + " does not require packing"
      case 2
     note nametab + " contains records without object"
     case 3
     note nametab + " requires packing (there are deleted records)"
     case 4
     note nametab + " requires packing (there are deleted records)" +chr$(10)+ " and contains records without object"
     case else
     note"Some trouble was encountered dealing with "+nametab
end case

end sub

Comments

This example calls also on the SelOpenTab() function

See also