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MySQL > Table doesn't exist. But it does (or it should)
...tory directly using command
cp -r /path/to/my/database /var/lib/mysql/new_database
If you do this with a database that uses InnoDB tables, you will get this crazy 'table does not exist' error mentioned above.
The issue is that you need the ib* files in the root of the MySQL datadir (e.g. ibdata...
What is @RenderSection in asp.net MVC
...
If you have a _Layout.cshtml view like this
<html>
<body>
@RenderBody()
@RenderSection("scripts", required: false)
</body>
</html>
then you can have an index.cshtml content view like this
...
'float' vs. 'double' precision
...54 bindings) is normative, but only in effect if an implementation defines __STDC_IEC_559__. An implementation that does not define that macro is free not to conform to IEEE-754.
– Stephen Canon
Feb 24 '11 at 0:06
...
C/C++ check if one bit is set in, i.e. int variable
...if you want to hide bit manipulation, you can write a macro:
#define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
and use it this way to check the nth bit from the right end:
CHECK_BIT(temp, n - 1)
In C++, you can use std::bitset.
...
OS X Bash, 'watch' command
...ulate the basic functionality with the shell loop:
while :; do clear; your_command; sleep 2; done
That will loop forever, clear the screen, run your command, and wait two seconds - the basic watch your_command implementation.
You can take this a step further and create a watch.sh script that can...
Converting NSString to NSDate (and back again)
...4, 17))
Goes like:
extension Date
{
public static func FromString(_ dateString: String) -> Date?
{
// Date detector.
let detector = try! NSDataDetector(types: NSTextCheckingResult.CheckingType.date.rawValue)
// Enumerate matches.
var matchedDate: Date...
Changing every value in a hash in Ruby
...ring objects):
# Two ways to achieve the same result (any Ruby version)
my_hash.each{ |_,str| str.gsub! /^|$/, '%' }
my_hash.each{ |_,str| str.replace "%#{str}%" }
If you want the hash to change in place, but you don't want to affect the strings (you want it to get new strings):
# Two ways to ac...
DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
...up.cfg file at the root directory of your project, usually where your main __init__.py or executable py file is. So if the root folder of your project is: /path/to/my/project/, create a setup.cfg file in there and put the magic words inside:
[install]
prefix=
OK, now you sould be able to run ...
Extracting just Month and Year separately from Pandas Datetime column
...
the best answer is clearly.. df['mnth_yr'] = df.date_column.dt.to_period('M') as below from @jaknap32
– ihightower
Jun 23 '17 at 6:16
1
...
How to solve the error LNK2019: unresolved external symbol - function?
...l but have not declared that class itself as import/export.
#ifdef MYDLL_EXPORTS
#define DLLEXPORT __declspec(dllexport)
#else
#define DLLEXPORT __declspec(dllimport)
#endif
class DLLEXPORT Book // <--- this class must also be declared as export/import
{
public:
Book();
...