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MYSQL OR vs IN performance
...elieve people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, though...
How to print a query string with parameter values when using Hibernate
... I am using grails 2.4.4 and hibernate 4. Changing log4j configuration did not work for me but p6spy worked!
– Champ
Jan 13 '15 at 7:03
11
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How do you copy a record in a SQL table but swap out the unique id of the new row?
...ce table and destination table are the same and the primary key is a uniqueidentifier (guid). When I try this:
11 Answers
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How do you dynamically add elements to a ListView on Android?
...e explain or suggest a tutorial to dynamically create a ListView in android?
7 Answers
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NullPointerException accessing views in onCreate()
...tion is to move the code to the fragment onCreateView(), calling findViewById() on the inflated fragment layout rootView:
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, cont...
When to add what indexes in a table in Rails
...
Should I add "index" to all the foreign keys like "xxx_id"?
It would be better, because it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be created automatically, for more informatio...
Change Active Menu Item on Page Scroll?
...ll position
var fromTop = $(this).scrollTop()+topMenuHeight;
// Get id of current scroll item
var cur = scrollItems.map(function(){
if ($(this).offset().top < fromTop)
return this;
});
// Get the id of the current element
cur = cur[cur.length-1];
var id = cur &am...
GCM with PHP (Google Cloud Messaging)
...
This code will send a GCM message to multiple registration IDs via PHP CURL.
// Payload data you want to send to Android device(s)
// (it will be accessible via intent extras)
$data = array('message' => 'Hello World!');
// The recipient registration tokens for this notifica...
Android - Set fragment id
How can I set a Fragment 's Id so that I can use getSupportFragmentManager().findFragmentById(R.id.--) ?
7 Answers
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How do I create a foreign key in SQL Server?
...
create table question_bank
(
question_id uniqueidentifier primary key,
question_exam_id uniqueidentifier not null,
question_text varchar(1024) not null,
question_point_value decimal,
constraint fk_questionbank_exams foreign key (question_exam_id) ...