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Is there any boolean type in Oracle databases?
...on about what to use instead. See this thread on asktom. From recommending CHAR(1) 'Y'/'N' they switch to NUMBER(1) 0/1 when someone points out that 'Y'/'N' depends on the English language, while e.g. German programmers might use 'J'/'N' instead.
The worst thing is that they defend this stupid deci...
Joining three tables using MySQL
...
SELECT
employees.id,
CONCAT(employees.f_name," ",employees.l_name) AS 'Full Name', genders.gender_name AS 'Sex',
depts.dept_name AS 'Team Name',
pay_grades.pay_grade_name AS 'Band',
designations.designation_name AS 'Role'
FROM employees
LE...
C++ Convert string (or char*) to wstring (or wchar_t*)
...nclude <string>
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
std::string narrow = converter.to_bytes(wide_utf16_source_string);
std::wstring wide = converter.from_bytes(narrow_utf8_source_string);
Longer online compilable and runnable example:
(They all sho...
Simple C example of doing an HTTP POST and consuming the response
...lude <netdb.h> /* struct hostent, gethostbyname */
void error(const char *msg) { perror(msg); exit(0); }
int main(int argc,char *argv[])
{
/* first what are we going to send and where are we going to send it? */
int portno = 80;
char *host = "api.somesite.com";
...
How do I URL encode a string
I have a URL string ( NSString ) with spaces and & characters. How do I url encode the entire string (including the & ampersand character and spaces)?
...
Reading a string with scanf
...tring[0]). On the other hand, scanf("%s", &string) passes a pointer-to-char[256], but it points to the same place.
Then scanf, when processing the tail of its argument list, will try to pull out a char *. That's the Right Thing when you've passed in string or &string[0], but when you've pas...
Is there a REAL performance difference between INT and VARCHAR primary keys?
Is there a measurable performance difference between using INT vs. VARCHAR as a primary key in MySQL? I'd like to use VARCHAR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
...
How to convert a number to string and vice versa in C++
...ersion succeeded and idx is not 0, idx will contain the index of the first character that was not used for decoding. This could be an index behind the last character.
Finally, the integral types allow to specify a base, for digits larger than 9, the alphabet is assumed (a=10 until z=35). You can fi...
How to open, read, and write from serial port in C?
...ed);
tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8; // 8-bit chars
// disable IGNBRK for mismatched speed tests; otherwise receive break
// as \000 chars
tty.c_iflag &= ~IGNBRK; // disable break processing
tty.c_lflag = 0; // n...
Java: notify() vs. notifyAll() all over again
...llowing sequence of events occurs - deadlock results:
STEP 1:
- P1 puts 1 char into the buffer
STEP 2:
- P2 attempts put - checks wait loop - already a char - waits
STEP 3:
- P3 attempts put - checks wait loop - already a char - waits
STEP 4:
- C1 attempts to get 1 char
- C2 attempts to get 1 c...