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Difference between JOIN and INNER JOIN
...nal,
or you can specify CROSS JOIN.
OR
For an inner join, the syntax is:
SELECT ...
FROM TableA
[INNER] JOIN TableB
(in other words, the "INNER" keyword is optional - results are the same
with or without it)
share
...
Rails :include vs. :joins
...
.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all the included tabl...
Xcode 6 - How to pick signing certificate/provisioning profile for Ad-Hoc distribution?
...ple.com and find the distribution provisioning profile you want to use.
2) Select it, click "Edit", re-name the profile, and click "Generate".
3) Download the provisioning profile to the Desktop and drag it onto the Xcode 6 icon.
4) Re-start Xcode 6.
5) Open the organizer window and click "Submit" o...
How to evaluate a math expression given in string form?
...r) {
return new Object() {
int pos = -1, ch;
void nextChar() {
ch = (++pos < str.length()) ? str.charAt(pos) : -1;
}
boolean eat(int charToEat) {
while (ch == ' ') nextChar();
if (ch == charToEat) {
nextChar...
Inserting multiple rows in mysql
...
it's also possible to use INSERT INTO Table SELECT 1, '14/05/2012', 3 UNION SELECT 2, '05/14/2012', 3. of course, this will only be better of the inserted values are coming from different tables.
– Zohar Peled
Jun 1 '15 at 9:18
...
jQuery Determine if a matched class has a given id
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You can bake that logic into the selector by combining multiple selectors. For instance, we could target all elements with a given id, that also have a particular class:
$("#foo.bar"); // Matches <div id="foo" class="bar">
This should look similar t...
How to use Servlets and Ajax?
...and execute the following function with Ajax response JSON...
var $select = $("#someselect"); // Locate HTML DOM element with ID "someselect".
$select.find("option").remove(); // Find all child elements with tag name "option" and rem...
Python: How to create a unique file name?
... answered Jun 2 '10 at 21:13
Richard BarrellRichard Barrell
4,01122 gold badges1919 silver badges1616 bronze badges
...
Why does base64 encoding require padding if the input length is not divisible by 3?
... either have to decode 4 bytes at a time or split the string after padding characters. It seems like those implementations just ignore the padding chars, even when they are in the middle of a string.
– Roman
May 30 at 7:02
...
MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
...
Rewrite the query into this
SELECT st1.*, st2.relevant_field FROM sometable st1
INNER JOIN sometable st2 ON (st1.relevant_field = st2.relevant_field)
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > 1
I think st2.relevant_...