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How to check if a map contains a key in Go?
...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope.
...
Database, Table and Column Naming Conventions? [closed]
... for Primary Key Columns, Hungarian-esque Constraint Prefixes and worst of all SPACES " " for multi-word table names. Additionally system tables for SQLServer use plurals so it seems AdventureWorks was the black sheep in this bunch.
– Marcus Pope
Mar 20 '12 at...
How to correctly use the extern keyword in C
...les: on variables it doesn't instantiate the variable itself, i.e. doesn't allocate any memory. This needs to be done somewhere else. Thus it's important if you want to import the variable from somewhere else. For functions, this only tells the compiler that linkage is extern. As this is the default...
How does collections.defaultdict work?
...
Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
Namespace not recognized (even though it is there)
... page.
This is a problem in Visual Studio (I would even go so far as to call it a bug). AutoMapper requires assemblies that are excluded from the .NET Framework 4 Client Profile. Since your project is using that version of the framework it breaks.
A similar error will propagate to the build pro...
Why rename synthesized properties in iOS with leading underscores? [duplicate]
...s is an artifact of a previous version of the Objective-C runtime.
Originally, @synthesize was used to create accessors methods, but the runtime still required that instance variables had to be instantiated explicitly:
@interface Foo : Bar {
Baz *_qux;
}
@property (retain) Baz *qux;
@end
@imp...
CSS table layout: why does table-row not accept a margin?
...ered Jan 2 '10 at 23:42
richardtallentrichardtallent
31.4k1313 gold badges7575 silver badges111111 bronze badges
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Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
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How to paste over without overwriting register
Does anyone know of a way to paste over a visually selected area without having the selection placed in the default register?
...
How to write header row with csv.DictWriter?
...ion "functionality", I'd prefer to code it myself; that way you can report ALL "extras" with the keys and values, not just the first extra key. What is a real nuisance with DictWriter is that if you've verified the keys yourself as each dict was being built, you need to remember to use extrasaction=...