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SQLAlchemy: What's the difference between flush() and commit()?
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A Session object is basically an ongoing transaction of changes to a database (update, insert, delete). These operations aren't persisted to the database until they are committed (if your program aborts for some reason in mid-session transaction, any...
Would it be beneficial to begin using instancetype instead of id?
...stancetype that, as far as I can see, replaces id as a return type in -alloc and init .
4 Answers
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How to clear basic authentication details in chrome
...password the last time you entered.
To use this trick, make sure to close all incognito windows. All incognito windows share the same cache. In other words, you cannot open multiple independent incognito windows. If you login in one of them and open another one, those two are related and you will s...
Getting the filenames of all files in a folder [duplicate]
I need to create a list with all names of the files in a folder.
3 Answers
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Update a record without first querying?
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@Gabriel Won't this update all properties though? What if I only want to modify a single one?
– David Pfeffer
Aug 15 '12 at 0:45
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What are the rules for evaluation order in Java?
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Let me say this very clearly, because people misunderstand this all the time:
Order of evaluation of subexpressions is independent of both associativity and precedence. Associativity and precedence determine in what order the operators are executed but do not determine in what order the ...
How to tell if a string is not defined in a Bash shell script
... not set, you can use:
if [ -z "${VAR+xxx}" ]; then echo VAR is not set at all; fi
if [ -z "$VAR" ] && [ "${VAR+xxx}" = "xxx" ]; then echo VAR is set but empty; fi
You probably can combine the two tests on the second line into one with:
if [ -z "$VAR" -a "${VAR+xxx}" = "xxx" ]; then echo VA...
How to search for occurrences of more than one space between words in a line
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Why are you using anchors at all? He's looking for spaces embedded somewhere in the lines.
– Tim Pietzcker
Sep 21 '10 at 9:43
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How to get the groups of a user in Active Directory? (c#, asp.net)
I use this code to get the groups of the current user. But I want to manually give the user and then get his groups. How can I do this?
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What is the difference between Directory.EnumerateFiles vs Directory.GetFiles?
...many files and directories, EnumerateFiles can be more efficient.
So basically, EnumerateFiles returns an IEnumerable which can be lazily evaluated somewhat, whereas GetFiles returns a string[] which has to be fully populated before it can return.
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