G
gus bjorklund
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> On Jun 30, 2017, at 1:18 PM, George Potemkin wrote: > > > And, are we sure that the WHERE FALSE is really doing all the same DB work? > > I'm sure. Checked with promon. > George, relying on memory, i can’t be entirely sure, but my guess is that what is happening is that in the true case, the selection logic decides to take the record and then: an icb (what the client's record buffer and related info is called) is being allocated and the record is copied into it. there is a small abount of (buffered) lbi activity related to this. since the loop is empty, the icb is deallocated and lbi data rewound. then the next iteration starts. i did a 2 part talk a while back called “Updating a record”. Part 2 explains what happens on the client side. can’t find it now.
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