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HTML select form with option to enter custom value
...users can enter custom text value or choose from drop down. A regular <select> only offers drop down options.
6 Ans...
What is meant by immutable?
...omething like this:
// Assume string is stored like this:
struct String { char* characters; unsigned int length; };
// Passing pointers because Java is pass-by-reference
struct String* substring(struct String* in, unsigned int begin, unsigned int end)
{
struct String* out = malloc(sizeof(struc...
Position of least significant bit that is set
...x077CB531U)) >> 27];
}
}
return total;
}
unsigned char lowestBitTable[256];
int get_lowest_set_bit(unsigned num) {
unsigned mask = 1;
for (int cnt = 1; cnt <= 32; cnt++, mask <<= 1) {
if (num & mask) {
return cnt;
}
}
...
PHP best way to MD5 multi-dimensional array?
...) function.
Test results for multi-dimensional array with md5-hashes (32 char) in keys and values:
Test name Repeats Result Performance
serialize 10000 0.761195 sec +0.00%
print_r 10000 1.669689 sec -119.35%
json_encode 10000...
Get list of databases from SQL Server
...
Execute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you pref...
How can I select an element with multiple classes in jQuery?
I want to select all the elements that have the two classes a and b .
13 Answers
13...
Insert, on duplicate update in PostgreSQL?
...try the UPDATE again
END;
END LOOP;
END;
$$
LANGUAGE plpgsql;
SELECT merge_db(1, 'david');
SELECT merge_db(1, 'dennis');
There's possibly an example of how to do this in bulk, using CTEs in 9.1 and above, in the hackers mailing list:
WITH foos AS (SELECT (UNNEST(%foo[])).*)
updated...
How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
...
Check if a row exists, otherwise insert
...
I assume a single row for each flight? If so:
IF EXISTS (SELECT * FROM Bookings WHERE FLightID = @Id)
BEGIN
--UPDATE HERE
END
ELSE
BEGIN
-- INSERT HERE
END
I assume what I said, as your way of doing things can overbook a flight, as it will insert a new row when there are 1...
How does UTF-8 “variable-width encoding” work?
... Like this:
0xxx xxxx A single-byte US-ASCII code (from the first 127 characters)
The multi-byte code-points each start with a few bits that essentially say "hey, you need to also read the next byte (or two, or three) to figure out what I am." They are:
110x xxxx One more byte follows
11...