Charlie Clark wrote:
SELECT count(attribute) FROM relatiin WHERE condition
Ah, okay, now I gotcha...
only returns 1 result so it's independent of LIMIT and result sets.
I wonder how the two methods compare efficiency-wise?
Yes, well, we're talking about MySQL specifically ;-)
Maybe although I sometimes why MySQL does anything: the documentation seems
to imply that many decisions were sort of "let's do it like this": cf.
particularly the recommendations for writing queries with JOINs. Personally I
do not see it as valid SQL to predicate a query on "what was just asked".
Sorry, not a lot of this paragraph made sense :-S
Regarding the original question: if I know I am working with LIMITs or result
sets then this implies I don't want to know the total size of the results
Not so. Think of batches:
"Now showing Results 5 - 10 of 25"
But why not just return all the rows and only show 5 of them?
"Now showing Results 5 - 10 of 250000"
Yes, it'll likely be a slower query anyway, but I can assure you, Zope
turning each of those rows into a Result object will be a LOT slower...
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