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Should I index a bit field in SQL Server?
...non-clustered indexes. My understanding of clustered indexes is that they group similar index values into the same page. This way when you ask for all the rows matching an index value, SQL can return those rows from a clustered page of memory. This is why trying to cluster index a GUID column is ...
How do I convert an interval into a number of hours with postgres?
...ch', order_time - '2016-09-05 00:00:00') / 3600)), count(*)
from od_a_week
group by floor((date_part('epoch', order_time - '2016-09-05 00:00:00') / 3600));
The ::int conversion follows the principle of rounding.
If you want a different result such as rounding down, you can use the corresponding ma...
Bulk package updates using Conda
...e it ready for testing we will post something on the mailing list (https://groups.google.com/forum/#!forum/spyderlib). Be sure to subscribe
Cheers!
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Showing a different background colour in Vim past 80 characters
...umns, and set colorcolumn for all columns from 1-80, and set the highlight group for colorcolumn to be the color you want your normal background to be.
– mkomitee
Jan 11 '12 at 13:20
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Difference between static and shared libraries?
...tional cost for execution of the functions" - that's possible (if function groups/ordering have been optimised for cache locality in the static link, or due to oddities in OS/loader/compiler/architecture like cross-segment/large-pointer perf. penalties), but on many architectures/compiler-settings t...
Creating an abstract class in Objective-C
...
From the Omni Group mailing list:
Objective-C doesn't have the abstract compiler construct like Java at
this time.
So all you do is define the abstract class as any other normal class
and implement methods stubs for the abstract methods ...
Returning multiple values from a C++ function
...ith a struct or class instance.
If they're not really related and can't be grouped into a class/struct then perhaps you should refactor your method into two.
Depending upon the in-memory size of the values you're returning, you may want to return a pointer to a class instance or struct, or use refer...
Why use String.Format? [duplicate]
...so the way five or more strings are joined via +s is by concatting them in groups of up to four, and then concatting those strings, and so on.
– octothorpentine
Aug 13 '15 at 18:46
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Search all tables, all columns for a specific value SQL Server [duplicate]
...Name, ColumnName, ColumnValue, ColumnType, COUNT(*) AS Count FROM #Results
GROUP BY TableName, ColumnName, ColumnValue, ColumnType
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Why is it important to override GetHashCode when Equals method is overridden?
...ce this is used (in the absence of a custom IEqualityComparer<T>) to group items into buckets. If the hash-code for two items does not match, they may never be considered equal (Equals will simply never be called).
The GetHashCode() method should reflect the Equals logic; the rules are:
if ...