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How do I retrieve my MySQL username and password?
...art the MySQL console client with the -u root option.
List all the users;
SELECT * FROM mysql.user;
Reset password;
UPDATE mysql.user SET Password=PASSWORD('[password]') WHERE User='[username]';
But DO NOT FORGET to
Stop the MySQL process
Start the MySQL Process normally (i.e. without the --ski...
MySQL: Large VARCHAR vs. TEXT?
... @Pacerier another interesting example is mentioned in the comments of the selected answer, basically he had a front-end limit of 2,000 characters but the characters introduced were in a codepage that in reality used more bytes than normal letters, his database ended up needing space for 24k charact...
What is the default value for enum variable?
...
Thanks, and what about enums defined with char instead of int. e.g. enum Status { Active = 'A', Inactive='I'}
– Fernando Torres
Apr 24 '15 at 16:17
...
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...
What are the main performance differences between varchar and nvarchar SQL Server data types?
... AND ([URLa] IS NULL OR [URLu] IS NULL))
);
In this model you only SELECT from the [URL] computed column. For inserting and updating, you determine which field to use by seeing if converting alters the incoming value, which has to be of NVARCHAR type:
INSERT INTO TableName (..., URLa, URLu)...
Limit number of characters allowed in form input text field
How do I limit or restrict the user to only enter a maximum of five characters in the textbox?
13 Answers
...
How can I use “sizeof” in a preprocessor macro?
...ou can use following macro:
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
Usage:
BUILD_BUG_ON( sizeof(someThing) != PAGE_SIZE );
This article explains in details why it works.
3. MS-specific
On Microsoft C++ compiler you can use C_ASSERT macro (requires #include &...
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";
...
Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column).
Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...
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...