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ERROR 1396 (HY000): Operation CREATE USER failed for 'jack'@'localhost'
.... I drop the user, flush, and then create, which fails with "ERROR 1396 (HY000) at line 7: Operation CREATE USER failed for ...". I wish I could get mysql/mariadb to elaborate a little bit on that error, like WHY it failed.
– David M. Karr
Mar 15 '17 at 20:08
...
Check if a given key already exists in a dictionary
...est you can run yourself. The results may astonish you. For dicts with ~50,000 keys, not calling keys() gives you .01 second computational benefit. For ~500,000 keys, not calling keys() gives you .1 second benefit. For ~5,000,000 keys, not calling keys() is .4 seconds faster, but for 50,000,000 keys...
How to remove newlines from beginning and end of a string?
...ot also a non-breaking space ('\u00A0', '\u2007', '\u202F').
It is '\t', U+0009 HORIZONTAL TABULATION.
It is '\n', U+000A LINE FEED.
It is '\u000B', U+000B VERTICAL TABULATION.
It is '\f', U+000C FORM FEED.
It is '\r', U+000D CARRIAGE RETURN.
It is '\u001C', U+001C FILE SEPARATOR.
It is '\u001D', U+...
Getting unique items from a list [duplicate]
...such as a Dictionary or HashSet. Because currently, if source contains 100,000 items with many duplicates, then in every one of the 100,000 iterations you will be scanning a list on the order of 100,000 items, meaning you are scanning on the order of 100,000 * 100,000 items. Quadratic time complexit...
How can I check if a Perl array contains a particular value?
...
Best general purpose - Especially short arrays (1000 items or less) and coders that are unsure of what optimizations best suit their needs.
# $value can be any regex. be safe
if ( grep( /^$value$/, @array ) ) {
print "found it";
}
It has been mentioned that grep passes...
Android SDK on a 64-bit linux machine
...m-tools$ ldd adb
linux-gate.so.1 => (0xf77bb000)
librt.so.1 => /lib/i386-linux-gnu/i686/cmov/librt.so.1 (0xf779b000)
libncurses.so.5 => not found
libpthread.so.0 => /lib/i386-linux-gnu/i686/cmov/libpthread.so.0 (0xf7781000)
libstdc++.so.6 =>...
Is this object-lifetime-extending-closure a C# compiler bug?
...ram/Foo/'<>c__DisplayClass1' 'CS$<>8__locals2'
)
IL_0000: newobj instance void ConsoleApplication1.Program/Foo/'<>c__DisplayClass1'::.ctor()
IL_0005: stloc.0
IL_0006: ldloc.0
IL_0007: ldarg.0
IL_0008: stfld class ConsoleApplication1.Program/Foo ConsoleApp...
How do you convert a byte array to a hexadecimal string, and vice versa?
... crude Stopwatch performance testing, a run with a random sentence (n=61, 1000 iterations) and a run with a Project Gutenburg text (n=1,238,957, 150 iterations). Here are the results, roughly from fastest to slowest. All measurements are in ticks (10,000 ticks = 1 ms) and all relative notes are comp...
Select random lines from a file
...
I ran this on a 500M row file to extract 1,000 rows and it took 13 min. The file had not been accessed in months, and is on an Amazon EC2 SSD Drive.
– T. Brian Jones
Mar 4 '16 at 18:26
...
Why does HTML think “chucknorris” is a color?
...lace all nonvalid hexadecimal characters with 0's
chucknorris becomes c00c0000000
Pad out to the next total number of characters divisible by 3 (11 -> 12)
c00c 0000 0000
Split into three equal groups, with each component representing the corresponding colour component of an RGB colour:
RGB (...