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>]) |
| Line 12: | Line 12: | ||
==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
