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Importance of varchar length in MySQL table
...serted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
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What is the proper way to re-attach detached objects in Hibernate?
...ale detached entity in JPA.
merge() will push the stale state to the DB,
and overwrite any intervening updates.
refresh() cannot be called on a detached entity.
lock() cannot be called on a detached entity,
and even if it could, and it did reattach the entity,
calling 'lock' with argument 'LockM...
How can I break an outer loop with PHP?
...outermost foreach
}
}
If you're in php >= 5.3, you can use labels and gotos, similar as in ActionScript:
foreach (...)
{
foreach (...)
{
if (i.name == j)
goto top;
}
}
top:
But goto must be used carefully. Goto is evil (considered bad practice)
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What is a good Hash Function?
What is a good Hash function? I saw a lot of hash function and applications in my data structures courses in college, but I mostly got that it's pretty hard to make a good hash function. As a rule of thumb to avoid collisions my professor said that:
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Gmail's new image caching is breaking image links in newsletter
...en this email will hit the gmail server GoogleImageProxy will try to fetch and store the images from your site to its own proxy server. while fetching the images, GoogleImageProxy found some 404 statuses against your missing images and 403 against some protected images. GoogleImagesProxy has stored ...
How to list only the file names that changed between two commits?
...ly HEAD~10 HEAD~5
to see the differences between the tenth latest commit and the fifth latest (or so).
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How can I compare two dates in PHP?
...n the database the date looks like this 2011-10-2
Store it in YYYY-MM-DD and then string comparison will work because '1' > '0', etc.
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How to paste text to end of every line? Sublime 2
...ous if there is a way to paste text to the end of every line in Sublime 2? And conversely, to the beginning of every line.
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Transpose list of lists
..., zip(*l)))
Explanation:
There are two things we need to know to understand what's going on:
The signature of zip: zip(*iterables) This means zip expects an arbitrary number of arguments each of which must be iterable. E.g. zip([1, 2], [3, 4], [5, 6]).
Unpacked argument lists: Given a sequence ...
Execute command on all files in a directory
...ich need to be run through a program. The program outputs the results to standard out. I need a script that will go into a directory, execute the command on each file, and concat the output into one big output file.
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