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Benchmarking small code samples in C#, can this implementation be improved?
Quite often on SO I find myself benchmarking small chunks of code to see which implemnetation is fastest.
11 Answers
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How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
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So what's the right answer here? Calling advance means we have to iterate the whole way through a possibly long string. But forming an NSRange and using NSString explicitly is dangerous? What's left?
– matt
Nov 18 '14 at...
Search for all occurrences of a string in a mysql database [duplicate]
I'm trying to figure out how to locate all occurrences of a url in a database. I want to search all tables and all fields. But I have no idea where to start or if it's even possible.
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How do I rotate the Android emulator display? [duplicate]
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Fn + Ctrl + F12, I really don't get why this get so many votes
– ericn
Apr 15 '13 at 1:10
13
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How do I find out which DOM element has the focus?
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Use document.activeElement, it is supported in all major browsers.
Previously, if you were trying to find out what form field has focus, you could not. To emulate detection within older browsers, add a "focus" event handler to all fields and record the last-focused field...
SSH Key - Still asking for password and passphrase
...ought I set it up. Is the ssh-agent something outside of git I need to install? Thanks
– HelloWorld
Jan 13 '14 at 15:50
2
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How to use multiple AWS Accounts from the command line?
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Maybe it still help someone. You can set it manually.
1) Set in file
~/.aws/credentials
this
[default]
aws_access_key_id={{aws_access_key_id}}
aws_secret_access_key={{aws_secret_access_key}}
[{{profile_name}}]
aws_access_key_id={{aws_access_key_id}}
aws_secret_access...
How to make child process die after parent exits?
... child process. Now when the parent process exits for whatever reason (normally or abnormally, by kill, ^C, assert failure or anything else) I want the child process to die. How to do that correctly?
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javac option to compile all java files under a given directory recursively
...oject and don't have any proper build tools nearby, you can always use a small trick that javac offers: the classnames to compile can be specified in a file. You simply have to pass the name of the file to javac with the @ prefix.
If you can create a list of all the *.java files in your project, it'...
How do I find which transaction is causing a “Waiting for table metadata lock” state?
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We can use INFORMATION_SCHEMA Tables.
Useful Queries
To check about all the locks transactions are waiting for:
USE INFORMATION_SCHEMA;
SELECT * FROM INNODB_LOCK_WAITS;
A list of blocking transactions:
SELECT *
FROM INNODB_LOCKS
WHERE LOCK_TRX_ID IN (SELECT BLOCKING_TRX_ID FROM INNODB_L...