Big processes movin/deleting/whatevering
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hundreds of thousands records may take long long time to be executed.
I've done it few times and I guess I'm not wrong to say that in an SQL based database you save time by simply doing for instance:
IF X<>"Value" THEN X:="Value"
instead of just:
X:=Value;
The big issue cames in C/SIDE. There's both data items where you may go faster with that modification and data items where you may instead go slower.
Does it ring a bell to someone?