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Generating a random & unique 8 character string using MySQL
...9f2a7baf3 => eccbc87e
etc.
caveat: I have no idea how many you could allocate before a collision (but it would be a known and constant value).
edit: This is now an old answer, but I saw it again with time on my hands, so, from observation...
Chance of all numbers = 2.35%
Chance of all lette...
How to run cron job every 2 hours
...into crontab :
crontab -e
write this into the file:
0 */2 * * * python/php/java yourfilepath
Example :0 */2 * * * python ec2-user/home/demo.py
and make sure you have keep one blank line after the last cron job in your crontab file
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What's the best practice to round a float to 2 decimals? [duplicate]
...ecimal instance multiple times each frame accounted for 99.9% of my memory allocations, so something to watch out for. In my opinion @Evan Stin's method 2 is the best answer, it's faster and doesn't leave anything behind.
– hamham
May 26 '16 at 8:56
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What is in your .vimrc? [closed]
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Refer to this script (vim.org/scripts/script.php?script_id=1349) to get the available colors. May need to turn on 256 color support for vim to get a wider variety.
– Brian Wigginton
Dec 13 '10 at 6:33
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Elasticsearch query to return all records
...e the scan+scroll-requests. If you do use size=BIGNUMBER, note that Lucene allocates memory for scores for that number, so don't make it exceedingly large. :)
– Alex Brasetvik
Nov 18 '13 at 19:33
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Conveniently Declaring Compile-Time Strings in C++
... nothing is appended sizeof(str) > i (instead of appending the extra 0, tokens)? It's easy to define a trim metafunction that will do this after the macro has already been called, but it would be nice if the macro itself could be modified.
– void-pointer
Apr...
Difference between char* and const char*?
...e points, as it could result in Undefined Behavior.
String literals may be allocated in read only memory regions (implementation defined) and an user program should not modify it in anyway. Any attempt to do so results in Undefined Behavior.
So the only difference in that case (of usage with s...
Making the Android emulator run faster
...for the AVD Manager to pick up the Intel Atom (x86) CPU option. Tip: Don't allocate too much RAM. With 1GB RAM, emulator failed to start (with GPU) but with 512MB RAM it ran smoothly and booted really quickly (again with GPU).
– ADTC
Jul 28 '13 at 16:11
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Can a pointer to base point to an array of derived objects?
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You cannot index like that. You have allocated an array of Rectangles and stored a pointer to the first in shapes. When you do shapes[1] you're dereferencing (shapes + 1). This will not give you a pointer to the next Rectangle, but a pointer to what would be the...
How can I troubleshoot my Perl CGI script?
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@derobert: actually, __DATA__ is the token used to start the data section, not __END__ (I think that was my confusion).
– Ether
Sep 9 '10 at 19:17
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