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What's the magic of “-” (a dash) in command-line parameters?
.../home | aescrypt -e -p apples -o backup_files.tar.aes - because the piping char | should make the presence of the last dash unnecessary. But without the last dash the command fails. Sounds illogical. Can someone please give me a reference where the naked dash meaning in command lines is explained. I...
How do I find a “gap” in running counter with SQL?
...
In MySQL and PostgreSQL:
SELECT id + 1
FROM mytable mo
WHERE NOT EXISTS
(
SELECT NULL
FROM mytable mi
WHERE mi.id = mo.id + 1
)
ORDER BY
id
LIMIT 1
In SQL Server:
SELECT TOP 1
i...
Efficient way to determine number of digits in an integer
...cialization optimization for 8-bit numbers
template <>
int numDigits(char n)
{
// if you have the time, replace this with a static initialization to avoid
// the initial overhead & unnecessary branch
static char x[256] = {0};
if (x[0] == 0) {
for (char c = 1; c != 0...
How can I limit possible inputs in a HTML5 “number” element?
...
@Prasad - If Andy's answer is correct, select it, instead of the most up voted one.
– Moshe
Dec 4 '11 at 14:47
81
...
How to get next/previous record in MySQL?
...
next:
select * from foo where id = (select min(id) from foo where id > 4)
previous:
select * from foo where id = (select max(id) from foo where id < 4)
...
How do you clear the SQL Server transaction log?
... solution then please comment below
Right click on the database name.
Select Tasks → Shrink → Database
Then click OK!
I usually open the Windows Explorer directory containing the database files, so I can immediately see the effect.
I was actually quite surprised this worked! Normally I'v...
How do I split a string with multiple separators in javascript?
...+/)
Hello,awesome,world!
Edited to add:
You can get the last element by selecting the length of the array minus 1:
>>> bits = "Hello awesome, world!".split(/[\s,]+/)
["Hello", "awesome", "world!"]
>>> bit = bits[bits.length - 1]
"world!"
... and if the pattern doesn't match:
...
Can I use a binary literal in C or C++?
...namespace std;
int main() {
unsigned short b = BOOST_BINARY( 10010 );
char buf[sizeof(b)*8+1];
printf("hex: %04x, dec: %u, oct: %06o, bin: %16s\n", b, b, b, itoa(b, buf, 2));
cout << setfill('0') <<
"hex: " << hex << setw(4) << b << ", " <<
...
How to reset postgres' primary key sequence when it falls out of sync?
...
-- Login to psql and run the following
-- What is the result?
SELECT MAX(id) FROM your_table;
-- Then run...
-- This should be higher than the last result.
SELECT nextval('your_table_id_seq');
-- If it's not higher... run this set the sequence last to your highest id.
-- (wise to run...
I need to store postal codes in a database. How big should the column be?
...nce a block on one side of the street. To find a broader region, you would select the first half of the postal code. Having this information in a separate table really won't help anything and would be more complicated to maintain.
– RevNoah
Dec 2 '13 at 17:08
...