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Types in MySQL: BigInt(20) vs Int(20)
...E TABLE foo ( bar INT(20) ZEROFILL );
INSERT INTO foo (bar) VALUES (1234);
SELECT bar from foo;
+----------------------+
| bar |
+----------------------+
| 00000000000000001234 |
+----------------------+
It's a common source of confusion for MySQL users to see INT(20) and assume ...
Simple way to encode a string according to a password?
... math.ceil(math.log(256 ** 32, 74)) == 42 characters long. However, a well-selected larger number of HMAC iterations can mitigate the lack of entropy somewhat as this makes it much more expensive for an attacker to brute force their way in.
Just know that choosing a shorter but still reasonably sec...
Passing base64 encoded strings in URL
...ed to url-encode it, since base64 strings can contain the "+", "=" and "/" characters which could alter the meaning of your data - look like a sub-folder.
Valid base64 characters are below.
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=
...
How to drop SQL default constraint without knowing its name?
...MySchema'
set @table_name = N'Department'
set @col_name = N'ModifiedDate'
select @Command = 'ALTER TABLE ' + @schema_name + '.[' + @table_name + '] DROP CONSTRAINT ' + d.name
from sys.tables t
join sys.default_constraints d on d.parent_object_id = t.object_id
join sys.columns c on c.object_id ...
Is the size of C “int” 2 bytes or 4 bytes?
...
"16 bits. In that case, int, is 2 bytes" can be wrong, if CHAR_BIT is 16, sizeof(int) can be 1 byte (or char).
– 12431234123412341234123
Mar 3 '17 at 14:55
6
...
How do I analyze a program's core dump file with GDB when it has command-line parameters?
... *(int*)(NULL) = i; /* line 7 */
return i - 1;
}
int main(int argc, char **argv) {
/* Setup some memory. */
char data_ptr[] = "string in data segment";
char *mmap_ptr;
char *text_ptr = "string in text segment";
(void)argv;
mmap_ptr = (char *)malloc(sizeof(data_ptr) + 1...
conditional unique constraint
... CheckActiveCount(
@Id INT
) RETURNS INT AS BEGIN
DECLARE @ret INT;
SELECT @ret = COUNT(*) FROM CheckConstraint WHERE Id = @Id AND RecordStatus = 1;
RETURN @ret;
END;
GO
ALTER TABLE CheckConstraint
ADD CONSTRAINT CheckActiveCountConstraint CHECK (NOT (dbo.CheckActiveCount(Id) > 1 AND...
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
...
How do you reverse a string in place in C or C++?
...
@fredsbend, the "ridiculously long" version of the selected answer handles a case which this simple answer doesn't - UTF-8 input. It shows the importance of fully specifying the problem. Besides the question was about code that would work in C as well.
–...
how to convert from int to char*?
...
In C++17, use std::to_chars as:
std::array<char, 10> str;
std::to_chars(str.data(), str.data() + str.size(), 42);
In C++11, use std::to_string as:
std::string s = std::to_string(number);
char const *pchar = s.c_str(); //use char const* a...