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Regular Expression to match only alphabetic characters
...z]+$/
to match an input string of ASCII alphabets.
[A-Za-z] will match all the alphabets (both lowercase and uppercase).
^ and $ will make sure that nothing but these alphabets will be matched.
Code:
preg_match('/^[A-Z]+$/i', "abcAbc^Xyz", $m);
var_dump($m);
Output:
array(0) {
}
Test cas...
List all tables in postgresql information_schema
What is the best way to list all of the tables within PostgreSQL's information_schema?
8 Answers
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Nullable Foreign Key bad practice?
... read.
Only if you know better than Chris Date "what first normal form really means". If x and y are both nullable, and indeed in some row x and y are both null, then WHERE x=y does not yield true. This proves beyond reasonable doubt that null is not a value (because any real value is always equ...
How do PHP sessions work? (not “how are they used?”)
...on files are usually stored in, say, /tmp/ on the server, and named sess_{session_id} . I have been looking at the contents and cannot figure out how they really work.
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How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?
...cessary instead of DateTime. So use Time.strptime("1318996912345",'%Q').to_f and you will see the milliseconds preserved, while DateTime.strptime("1318996912345",'%Q').to_f does not preserve it.
– skensell
Feb 22 '17 at 15:20
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In CMake, how can I test if the compiler is Clang?
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A reliable check is to use the CMAKE_<LANG>_COMPILER_ID variables. E.g., to check the C++ compiler:
if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
# using Clang
elseif (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
# using GCC
elseif (CMAKE_CXX_COMPILER_ID STREQ...
Setting WPF image source in code
...packUri = "pack://application:,,,/AssemblyName;component/Images/icon.png";
_image.Source = new ImageSourceConverter().ConvertFromString(packUri) as ImageSource;
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user authentication libraries for node.js?
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Among all auth packages for node I selected passport. It's well-documented and easy to use, and supports more strategies.
– tech-man
May 14 '12 at 4:16
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reference assignment is atomic so why is Interlocked.Exchange(ref Object, Object) needed?
In my multithreaded asmx web service I had a class field _allData of my own type SystemData which consists of few List<T> and Dictionary<T> marked as volatile . The system data ( _allData ) is refreshed once in a while and I do it by creating another object called newData and fill...
Mutex example / tutorial? [closed]
... The first person to catch the door-handle of the booth, is the one who is allowed to use the phone. He has to keep holding on to the handle of the door as long as he uses the phone, otherwise someone else will catch hold of the handle, throw him out and talk to his wife :) There's no queue system a...