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C++ performance challenge: integer to std::string conversion
...
#include <string>
const char digit_pairs[201] = {
"00010203040506070809"
"10111213141516171819"
"20212223242526272829"
"30313233343536373839"
"40414243444546474849"
"50515253545556575859"
"60616263646566676869"
"70717273747576777879"...
PreparedStatement IN clause alternatives?
... and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful.
Prepare SELECT my_column FROM my_table WHERE search_...
How to truncate string using SQL server
...ou only want to return a few characters of your long string, you can use:
select
left(col, 15) + '...' col
from yourtable
See SQL Fiddle with Demo.
This will return the first 15 characters of the string and then concatenates the ... to the end of it.
If you want to to make sure than strings ...
Implicit type conversion rules in C++ operators
...re promoted to int
Note. The minimum size of operations is int. So short/char are promoted to int before the operation is done.
In all your expressions the int is promoted to a float before the operation is performed. The result of the operation is a float.
int + float => float + float = flo...
Difference between Char.IsDigit() and Char.IsNumber() in C#
What's the difference between Char.IsDigit() and Char.IsNumber() in C#?
3 Answers
...
What's the rationale for null terminated strings?
...
From the horse's mouth
None of BCPL, B, or C supports
character data strongly in the
language; each treats strings much
like vectors of integers and
supplements general rules by a few
conventions. In both BCPL and B a
string literal denotes the address of
a static ar...
error C2440: \'initializing\' : cannot convert from \'char *\' to \'co...
error C2440: 'initializing' : cannot convert from 'char *' to 'const class std::basic_string *'error C2440: 'initializing' : cannot convert from 'char *' to 'const class std::basic_string<char,...error C2440: 'initializing' : cannot convert from 'char *' to 'const class std::basic_string<char,struct...
Get first n characters of a string
How can I get the first n characters of a string in PHP? What's the fastest way to trim a string to a specific number of characters, and append '...' if needed?
...
Replace a character at a specific index in a string?
I'm trying to replace a character at a specific index in a string.
8 Answers
8
...
How do you allow spaces to be entered using scanf?
...
/* Maximum name size + 1. */
#define MAX_NAME_SZ 256
int main(int argC, char *argV[]) {
/* Allocate memory and check if okay. */
char *name = malloc(MAX_NAME_SZ);
if (name == NULL) {
printf("No memory\n");
return 1;
}
/* Ask user for name. */
printf("Wha...