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MIN/MAX vs ORDER BY and LIMIT
...d field, using MIN() requires a single full pass of the table. Using SORT and LIMIT requires a filesort. If run against a large table, there would likely be a significant difference in percieved performance. As a meaningless data point, MIN() took .36s while SORT and LIMIT took .84s against a 106...
How to generate a random number between a and b in Ruby?
To generate a random number between 3 and 10, for example, I use: rand(8) + 3
8 Answers
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Asking the user for input until they give a valid response
...put the input method in a while loop. Use continue when you get bad input, and break out of the loop when you're satisfied.
When Your Input Might Raise an Exception
Use try and except to detect when the user enters data that can't be parsed.
while True:
try:
# Note: Python 2.x users s...
How do I update a Linq to SQL dbml file?
...to keep the model in sync.
Delete the modified tables from the designer, and drag them back onto the designer surface from the Database Explorer. I have found that, for this to work reliably, you have to:
a. Refresh the database schema in the Database Explorer (right-click, refresh)
b. Save th...
Detect URLs in text with JavaScript
...ou need a good regex that matches urls. This is hard to do. See here, here and here:
...almost anything is a valid URL. There
are some punctuation rules for
splitting it up. Absent any
punctuation, you still have a valid
URL.
Check the RFC carefully and see if you
can construct ...
.gitignore and “The following untracked working tree files would be overwritten by checkout”
.... The --cached will prevent it from having any effect on your working copy and it will just mark as removed the next time you commit. After the files are removed from the repo then the .gitignore will prevent them from being added again.
But you have another problem with your .gitignore, you are ex...
jQuery UI Sortable, then write order into a database
...nt to use the jQuery UI sortable function to allow users to set an order and then on change, write it to the database and update it. Can someone write an example on how this would be done?
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'float' vs. 'double' precision
... in C use IEEE 754 encoding.
This type of encoding uses a sign, a significand, and an exponent.
Because of this encoding, many numbers will have small changes to allow them to be stored.
Also, the number of significant digits can change slightly since it is a binary representation, not a decimal ...
Difference between ObservableCollection and BindingList
I want to know the difference between ObservableCollection and BindingList because I've used both to notify for any add/delete change in Source, but I actually do not know when to prefer one over the other.
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Setting git parent pointer to a different parent
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Using git rebase. It's the generic "take commit(s) and plop it/them on a different parent (base)" command in Git.
Some things to know, however:
Since commit SHAs involve their parents, when you change the parent of a given commit, its SHA will change - as will the SHAs of ...