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print call stack in C or C++
...oid my_func_1(int i) {
(void)i;
my_func_2();
}
int main(int argc, char **argv) {
long long unsigned int n;
if (argc > 1) {
n = strtoul(argv[1], NULL, 0);
} else {
n = 1;
}
for (long long unsigned int i = 0; i < n; ++i) {
my_func_1(1); // l...
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...
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...
Get all table names of a particular database by SQL query?
...n I have different table schemata within one database (SQL Server): SELECT CONCAT(TABLE_SCHEMA, '.', TABLE_NAME) FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_CATALOG='MyDB'
– Verena Haunschmid
Aug 10 '15 at 8:08
...
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";
...
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...
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)?
...
How to see full query from SHOW PROCESSLIST
...; the capacity to end a query on Amazon Aurora MySQL: select id pid, user, concat('CALL mysql.rds_kill(', id, ');'), time, state, info from information_schema.processlist where info is not null order by time desc;
– spen.smith
Sep 9 at 23:35
...
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...