Difference between revisions of "OLDVAL()"

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==Purpose==
 
==Purpose==
Function to  
+
Function to to return original values for fields that may have been modified but not updated
  
  
 
==Syntax==
 
==Syntax==
OLDVAL()
+
OLDVAL(<expC> [, <workarea | alias>])
  
  
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==Description==
 
==Description==
 +
The OLDVAL() function can be used during buffered processing to return one or more field values from a record as they were prior to any uncommitted changes. The field or fields to be checked are specified in <expC>.
  
 +
If the optional <workarea | alias> is specified, then the function will operate in the required location.
  
  
 
==Example==
 
==Example==
 
<code lang="recital">
 
<code lang="recital">
 +
close databases
 +
clear
 +
set exclusive off
 +
open database southwind
 +
use customers
 +
// Set to known value before start
 +
replace customerid with "ALFKI"
  
 +
cursorsetprop("Buffering", 5, "customers")
 +
messagebox("Buffering set to " +etos(cursorgetprop("Buffering")))
 +
 +
? "Original customerid value: " + customerid
 +
? "Curval(): " + curval("customerid")
 +
? "Oldval(): " + oldval("customerid")
 +
? "Fieldstate at start: " + getfldstate("customerid")
 +
 +
replace customerid WITH "RECIT"
 +
 +
// Alter in another session
 +
! recital -c "update southwind\!customers set customerid = 'MULTI' where recno() = 1"
 +
? "Someone else just updated the record!"
 +
? "New customerid value: " +  customerid
 +
? "Curval(): " + curval("customerid")
 +
? "Oldval(): " + oldval("customerid")
 +
? "Fieldstate after replace: " + getfldstate("customerid")
 +
tablerevert(.T.)
 +
 +
? "Reverted customerid value: " +  customerid
 +
? "Curval(): " + curval("customerid")
 +
? "Oldval(): " + oldval("customerid")
 +
? "Fieldstate after revert: " + getfldstate("customerid")
 +
 +
replace customerid WITH "RECIT"
 +
? "New customerid value: " +  customerid
 +
tableupdate(.T.)
 +
? "Updated customerid value: " +  customerid
 +
? "Curval(): " + curval("customerid")
 +
? "Oldval(): " + oldval("customerid")
 +
? "Fieldstate after replace and update: " + getfldstate("customerid")
 +
?
 
</code>
 
</code>
  

Latest revision as of 12:34, 22 August 2011

Purpose

Function to to return original values for fields that may have been modified but not updated


Syntax

OLDVAL(<expC> [, <workarea | alias>])


See Also

CURSORGETPROP(), CURSORSETPROP(), CURVAL(), GETFLDSTATE(), TABLEREVERT(), TABLEUPDATE(), SETFLDSTATE()


Description

The OLDVAL() function can be used during buffered processing to return one or more field values from a record as they were prior to any uncommitted changes. The field or fields to be checked are specified in <expC>.

If the optional <workarea | alias> is specified, then the function will operate in the required location.


Example

close databases
clear
set exclusive off
open database southwind
use customers
// Set to known value before start
replace customerid with "ALFKI"
 
cursorsetprop("Buffering", 5, "customers")
messagebox("Buffering set to " +etos(cursorgetprop("Buffering")))
 
? "Original customerid value: " + customerid
? "Curval(): " + curval("customerid")
? "Oldval(): " + oldval("customerid")
? "Fieldstate at start: " + getfldstate("customerid")
 
replace customerid WITH "RECIT"
 
// Alter in another session
! recital -c "update southwind\!customers set customerid = 'MULTI' where recno() = 1"
? "Someone else just updated the record!"
? "New customerid value: " +  customerid 
? "Curval(): " + curval("customerid")
? "Oldval(): " + oldval("customerid")
? "Fieldstate after replace: " + getfldstate("customerid")
tablerevert(.T.)
 
? "Reverted customerid value: " +  customerid
? "Curval(): " + curval("customerid")
? "Oldval(): " + oldval("customerid")
? "Fieldstate after revert: " + getfldstate("customerid")
 
replace customerid WITH "RECIT"
? "New customerid value: " +  customerid 
tableupdate(.T.)
? "Updated customerid value: " +  customerid
? "Curval(): " + curval("customerid")
? "Oldval(): " + oldval("customerid")
? "Fieldstate after replace and update: " + getfldstate("customerid")
?


Products

Recital, Recital Server