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ROW_NUMBER() in MySQL
...e about that in the answer a tic ago. You can usually easily drop unwanted extra rows in the application layer afterwards on some random basis, but if you have a lot of rows all with the same col3 it can be problematic.
– bobince
Dec 13 '09 at 0:18
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Check if a String contains numbers Java
I'm writing a program where the user enters a String in the following format:
14 Answers
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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...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
...s infinitely safer than using escaping functions such as mysql_real_escape_string.
Yes, mysql_real_escape_string is effectively just a string escaping function. It is not a magic bullet. All it will do is escape dangerous characters in order that they can be safe to use in a single query string. Ho...
How to handle Objective-C protocols that contain properties?
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@interface MyClass () // Class extension
@property (nonatomic, strong) NSString *name;
@end
How to use property in protocol
So to use MyClass with that name property, we have to do either
Declare the property again (AppDelegate.h does this way)
@interface MyClass : NSObject <MyProtocol&...
Storing sex (gender) in database
... space savings, it only pays off if you have multiple bit fields.
Second, strings/chars have a "magic value" feel to them, regardless of how obvious they may seem at design time. Not to mention, it lets people store just about any value they would not necessarily map to anything obvious.
Third, a ...
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...
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.
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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...
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...