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What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
What are the different cases when we use these three? Where should I use one and where should I not?
9 Answers
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Javascript: best Singleton pattern [duplicate]
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"It won't if"... please, anyone still could overwrite the singleton by e.g. injecting javascript trough a bookmarklet/favlet when not using the closure pattern. It's not just about you using your own code properly, but also about avoiding malicious atta...
MySQL Error 1215: Cannot add foreign key constraint
...ing to use as a foreign key are primary keys in their own tables. I have done both of these things, if I'm not mistaken. Any other help you guys could offer?
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Best way to convert strings to symbols in hash
...my_hash.transform_keys(&:to_sym)
Using older Ruby version? Here is a one-liner that will copy the hash into a new one with the keys symbolized:
my_hash = my_hash.inject({}){|memo,(k,v)| memo[k.to_sym] = v; memo}
With Rails you can use:
my_hash.symbolize_keys
my_hash.deep_symbolize_keys
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What is a patch in git version control?
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A good answer, and one that tells me that a GIT 'patch' is not what I'm looking for.
– RonLugge
Feb 17 '12 at 18:49
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__getattr__ on a module
...ort time) should be no longer necessary.
In Python 3.7+, you just use the one obvious way. To customize attribute access on a module, define a __getattr__ function at the module level which should accept one argument (name of attribute), and return the computed value or raise an AttributeError:
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Draw line in UIView
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Does one not need to call CGContextBeginPath(context); before CGContextMoveToPoint(...);?
– i_am_jorf
Nov 9 '11 at 18:38
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VIM Replace word with contents of paste buffer?
..., not an EX command such as :%s///g . I know that this is the typical way one replaces the word at the current cursor position: cw<text><esc> but is there a way to do this with the contents of the unnamed register as the replacement text and without overwriting the register?
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Why are side-effects modeled as monads in Haskell?
Could anyone give some pointers on why the impure computations in Haskell are modelled as monads?
8 Answers
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How do I properly force a Git push?
I've set up a remote non-bare "main" repo and cloned it to my computer. I made some local changes, updated my local repository, and pushed the changes back to my remote repo. Things were fine up to that point.
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