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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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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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A numeric string as array key in PHP
...around is:
$id = 55;
$array = array(
" $id" => $value
);
The space char (prepend) is a good solution because keep the int conversion:
foreach( $array as $key => $value ) {
echo $key;
}
You'll see 55 as int.
s...
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...
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 is the best way to test for an empty string in Go?
...tever, since len() has to execute to completion.
– Richard
Apr 30 '18 at 11:25
Have you looked at the code generation ...
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 ...
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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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)
...
Displaying better error message than “No JSON object could be decoded”
......
simplejson.decoder.JSONDecodeError: Expecting object: line 1 column 5 (char 5)
Much better! Likewise for other common errors like capitalizing True.
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