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What does “O(1) access time” mean?
I have seen this term "O(1) access time" used to mean "quickly" but I don't understand what it means. The other term that I see with it in the same context is "O(n) access time". Could someone please explain in a simple way what these terms mean?
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What GRANT USAGE ON SCHEMA exactly do?
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GRANTs on different objects are separate. GRANTing on a database doesn't GRANT rights to the s...
Executing elements inserted with .innerHTML
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answered Jul 14 '10 at 20:48
Larry KLarry K
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How do I concatenate two strings in C?
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Counting null and non-null values in a single query
... to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us;
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How do I convert a string to a number in PHP?
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You don't typically need to do this, since PHP will coerce the type for you in most circumsta...
How do I find the install time and date of Windows?
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How do I test for an empty JavaScript object?
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How to create a circular ImageView in Android? [duplicate]
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