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What is the difference between varchar and varchar2 in Oracle?
...ARCHAR is reserved by Oracle to support distinction between NULL and empty string in future, as ANSI standard prescribes.
VARCHAR2 does not distinguish between a NULL and empty string, and never will.
If you rely on empty string and NULL being the same thing, you should use VARCHAR2.
...
Why would one omit the close tag?
...hp closing tag (?>) is so that the programmer doesn't accidentally send extra newline chars.
The reason you shouldn't leave off the php closing tag is because it causes an imbalance in the php tags and any programmer with half a mind can remember to not add extra white-space.
So for your questi...
How to trick an application into thinking its stdout is a terminal, not a pipe
...ript command does what we want...
script --return --quiet -c "[executable string]" /dev/null
Does the trick!
Usage:
script [options] [file]
Make a typescript of a terminal session.
Options:
-a, --append append the output
-c, --command <command> run command rathe...
Common MySQL fields and their appropriate data types
... |
| salt | CHAR(x) | randomly generated string, usually of
fixed length (x)
| digest (md5) | CHAR(32) | |
| phone number | VAR...
How to convert int to char with leading zeros?
..."Len()" function works on ints, so there's no need to convert the int to a string before calling the len() function.
Lastly, you are not taking into account the case where the size of your int > the total number of digits you want it padded to (@intLen).
Therefore, a more concise / correct solu...
How can I convert tabs to spaces in every file of a directory?
...
DO NOT USE SED! If there's an embedded tab in a string, you may end up mangling your code. This is what expand command was meant to handle. Use expand.
– David W.
Nov 12 '13 at 17:11
...
Variable declaration placement in C
...ation and initialization of a C++ local object then you pay the cost of an extra constructor for nothing. If the no-arg constructor does not exist then again you are not even allowed to separate both!
C99 starts to move C in this same direction.
If you are worried of not finding where local varia...
LINQ: “contains” and a Lambda query
... open,
closed,
weird,
};
public string Name { get; set; }
public StatusType Status { get; set; }
}
public static List <Building> buildingList = new List<Building> ()
{
new Building () { Name = "one", Status = Buildin...
node.js execute system command synchronously
...re("node-ffi");
var libc = new FFI.Library(null, {
"system": ["int32", ["string"]]
});
var run = libc.system;
run("echo $USER");
[EDIT Jun 2012: How to get STDOUT]
var lib = ffi.Library(null, {
// FILE* popen(char* cmd, char* mode);
popen: ['pointer', ['string', 'string']],
// voi...
How do pointer to pointers work in C?
...--+----+----+----+----+
What you can see here, is that at address 63 the string "hello" starts. So in this case, if this is the only occurrence of "hello" in memory then,
const char *c = "hello";
... defines c to be a pointer to the (read-only) string "hello", and thus contains the value 63. c ...