Difference between revisions of "CURVAL()"
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==Purpose== | ==Purpose== | ||
Function to return field values directly from disk | Function to return field values directly from disk | ||
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==Syntax== | ==Syntax== | ||
CURVAL(<expC> [, <workarea | alias>]) | CURVAL(<expC> [, <workarea | alias>]) | ||
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==See Also== | ==See Also== | ||
[[CURSORGETPROP()]], [[CURSORSETPROP()]], [[GETFLDSTATE()]], [[OLDVAL()]], [[TABLEREVERT()]], [[TABLEUPDATE()]], [[SETFLDSTATE()]] | [[CURSORGETPROP()]], [[CURSORSETPROP()]], [[GETFLDSTATE()]], [[OLDVAL()]], [[TABLEREVERT()]], [[TABLEUPDATE()]], [[SETFLDSTATE()]] | ||
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==Description== | ==Description== | ||
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If the optional <workarea | alias> is specified, then the function will operate in the required location. | If the optional <workarea | alias> is specified, then the function will operate in the required location. | ||
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==Example== | ==Example== | ||
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? "Fieldstate at start: " + getfldstate("customerid") | ? "Fieldstate at start: " + getfldstate("customerid") | ||
| − | replace customerid WITH " | + | replace customerid WITH "LIANJ" |
// Alter in another session | // Alter in another session | ||
| − | + | // update southwind!customers set customerid = 'MULTI' where recno() = 1 | |
? "Someone else just updated the record!" | ? "Someone else just updated the record!" | ||
? "New customerid value: " + customerid | ? "New customerid value: " + customerid | ||
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? "Fieldstate after revert: " + getfldstate("customerid") | ? "Fieldstate after revert: " + getfldstate("customerid") | ||
| − | replace customerid WITH " | + | replace customerid WITH "LIANJ" |
? "New customerid value: " + customerid | ? "New customerid value: " + customerid | ||
tableupdate(.T.) | tableupdate(.T.) | ||
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</code> | </code> | ||
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[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:Functions]] | [[Category:Functions]] | ||
| − | [[Category: | + | [[Category:Cursor Functions]] |
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Latest revision as of 13:37, 19 May 2014
Contents
Purpose
Function to return field values directly from disk
Syntax
CURVAL(<expC> [, <workarea | alias>])
See Also
CURSORGETPROP(), CURSORSETPROP(), GETFLDSTATE(), OLDVAL(), TABLEREVERT(), TABLEUPDATE(), SETFLDSTATE()
Description
The CURVAL() function can be used to return one or more field values directly from disk. During buffered processing, this allows checks to be made for changes to the data, since the record was accessed. 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 "LIANJ" // Alter in another session // 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 "LIANJ" ? "New customerid value: " + customerid tableupdate(.T.) ? "Updated customerid value: " + customerid ? "Curval(): " + curval("customerid") ? "Oldval(): " + oldval("customerid") ? "Fieldstate after replace and update: " + getfldstate("customerid") ?
