Sometimes for debug purposes it is helpful to add a char prefix
to specific column in a SQL table. Then when debug is complete you want to
undo that prefix. In the example below the prefix char is the percent
sign.
update myTable set myColumn = '%' + myColumn where ...
Then to undo
update myTable set myColumn = myColumn ( myColumn ,2 , len(myColumn) -1 )
Where SUBSTRING ( DISPLAY ,1 , 1 ) = '%' AND the where clause you used above
See also
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