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What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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Can someone explain collection_select to me in clear, simple terms?
I am going through the Rails API docs for collection_select and they are god-awful.
2 Answers
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Oracle SQL: Update a table with data from another table
...his is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2
WHERE t1.id = t2.id )
Assuming the join results in a key-pr...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
how to get html content from a webview?
...ion con = url.openConnection();
Pattern p = Pattern.compile("text/html;\\s+charset=([^\\s]+)\\s*");
Matcher m = p.matcher(con.getContentType());
/* If Content-Type doesn't match this pre-conception, choose default and
* hope for the best. */
String charset = m.matches() ? m.group(1) : "ISO-8859-1"...
Replace console output in Python
...t of the bar.
def startprogress(title):
"""Creates a progress bar 40 chars long on the console
and moves cursor back to beginning with BS character"""
global progress_x
sys.stdout.write(title + ": [" + "-" * 40 + "]" + chr(8) * 41)
sys.stdout.flush()
progress_x = 0
def pr...
Grep characters before and after match?
...
3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
share
|
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Select text on input focus
I have a text input. When the input receives focus I want to select the text inside of the input.
10 Answers
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postgresql: INSERT INTO … (SELECT * …)
...ostgres
CREATE TABLE tblA (id serial, time integer);
INSERT INTO tblA
SELECT id, time
FROM dblink('dbname=dbtest', 'SELECT id, time FROM tblB')
AS t(id integer, time integer)
WHERE time > 1000;
TABLE tblA;
id | time
----+------
1 | 5000
2 | 2000
(2 rows)
PostgreSQL has ...
How do I use variables in Oracle SQL Developer?
... other stuff didn't work for me, but this did:
define value1 = 'sysdate'
SELECT &&value1 from dual;
Also it's the slickest way presented here, yet.
(If you omit the "define"-part you'll be prompted for that value)
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