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Difference between BYTE and CHAR in column datatypes
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Let us assume the database character set is UTF-8, which is the recommended setting in recent versions of Oracle. In this case, some characters take more than 1 byte to store in the database.
If you define the field as VARCHAR2(11 BYTE), Oracle can us...
How can I validate a string to only allow alphanumeric characters in it?
...n I validate a string using Regular Expressions to only allow alphanumeric characters in it?
10 Answers
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How do I tokenize a string in C++?
...enizer.hpp>
using namespace std;
using namespace boost;
int main(int, char**)
{
string text = "token, test string";
char_separator<char> sep(", ");
tokenizer< char_separator<char> > tokens(text, sep);
BOOST_FOREACH (const string& t, tokens) {
cou...
Is there an auto increment in sqlite?
... In case it is not obvious from answer, you can use ROWID in your select statement e.g. select rowid from people;
– Colin D
Mar 20 '17 at 15:37
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strdup() - what does it do in C?
...'s a POSIX thing), it's effectively doing the same as the following code:
char *strdup(const char *src) {
char *dst = malloc(strlen (src) + 1); // Space for length plus nul
if (dst == NULL) return NULL; // No memory
strcpy(dst, src); // Copy the characters...
Convert character to ASCII numeric value in java
I have String name = "admin";
then I do String charValue = name.substring(0,1); //charValue="a"
22 Answers
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NULL values inside NOT IN clause
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Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <&...
What type of hash does WordPress use?
...have access to the DB, using MyPHPAdmin you can change the PW to "MyPass", select MD5 in the "Function" dropdown and it will save as a straight MD5. Sign into Wordpress, and it will change it to the "salted" version with the $P$B__/ added.
– BillyNair
Oct 26 '1...
What is the difference between static_cast and C style casting?
...situations where all that is needed is a simple conversion. The ability to select between several different casting operators of differing degrees of power can prevent programmers from inadvertently casting to an incorrect type.
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How to change string into QString?
...QString::fromStdString(str);
If by string you mean Ascii encoded const char * then you can use this method:
QString QString::fromAscii(const char * str, int size = -1)
const char* str = "Hello world";
QString qstr = QString::fromAscii(str);
If you have const char * encoded with system enco...