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Maximum number of records in a MySQL database table
...g with multiple billions of entries? (which would probably just make your select statements melt down long before then)
– Kzqai
Apr 26 '10 at 19:35
2
...
What is the use of the %n format specifier in C?
...inted. The argument must be a pointer to a signed int, where the number of characters written so far is stored.
#include <stdio.h>
int main()
{
int val;
printf("blah %n blah\n", &val);
printf("val = %d\n", val);
return 0;
}
The previous code prints:
blah blah
val = 5
...
深入浅出计算机字符集编码 - C/C++ - 清泛网 - 专注C/C++及内核技术
...二进制内容,不同的编码环境下显示不一致:
unsigned char j = 0xa1;
for(; j < 0xdf-30; j++)
{
char p[1024];
sprintf(p, "%d\t%02x\t%o\t%c \t %d\t%02x\t%o\t%c", j,j,j,j, j+31,j+31,j+31,j+31);
std::cout << p << std::endl;
}
(整形,十六进制,八进制,字符...
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...compared using a comparison operator such as =, <> or IS NULL. e.g.
SELECT
a.answer_body
FROM answers AS a
WHERE a.is_accepted = 0;
From a formatting perspective, a bit value is typically displayed as 0 or 1 in client software. When a more user-friendly format is required, and it can't ...
How does strtok() split the string into tokens in C?
...one token becomes the starting token of the next token?also is there a nul character placed in the place of the ending condition?
– user379888
Oct 8 '10 at 12:32
1
...
Finding three elements in an array whose sum is closest to a given number
...We've found the answer.
The sum was too small. Move j closer to the end to select the next biggest number.
The sum was too big. Move k closer to the beginning to select the next smallest number.
For each i, the pointers of j and k will gradually get closer to each other. Eventually they will pass ...
TLSF源码及算法介绍 - 开源 & Github - 清泛网 - 专注C/C++及内核技术
...(0xFFFFFFFF - PTR_MASK)
#define GET_NEXT_BLOCK(_addr, _r) ((bhdr_t *) ((char *) (_addr) + (_r)))
#define MEM_ALIGN ((BLOCK_ALIGN) - 1)
#define ROUNDUP_SIZE(_r) (((_r) + MEM_ALIGN) & ~MEM_ALIGN)
#define ROUNDDOWN_SIZE(_r) ((_r) & ~MEM_ALIGN)
#define ROUNDUP(_x, _v) ...
Difference between string and text in rails?
... load varchar in one go, but store text (and blob) outside of the table. A SELECT name, amount FROM products could, be a lot slower when using text for name than when you use varchar. And since Rails, by default loads records with SELECT * FROM... your text-columns will be loaded. This will probably...
Remove spaces from std::string in C++
...ed way to remove spaces from a string in C++? I could loop through all the characters and build a new string, but is there a better way?
...
How can I read and parse CSV files in C++?
...0E+09
The code is written as a finite-state machine and is consuming one character at a time. I think it's easier to reason about.
#include <istream>
#include <string>
#include <vector>
enum class CSVState {
UnquotedField,
QuotedField,
QuotedQuote
};
std::vector<...