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CSS Child vs Descendant selectors
I am a bit confused between these 2 selectors.
8 Answers
8
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SQL how to make null values come last when sorting ascending
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select MyDate
from MyTable
order by case when MyDate is null then 1 else 0 end, MyDate
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Is there any performance gain in indexing a boolean field?
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It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
... a query, specifically the position where a reader is in a ResultSet. Each SELECT statement has a cursor, and PL/SQL stored procedures can open and use as many cursors as they require. You can find out more about cursors on Orafaq.
A database instance typically serves several different schemas, man...
PHP MySQL Google Chart JSON - Complete Example
... else
{
//echo ("Connect Successfully");
}
$query = "SELECT Date_time, Tempout FROM alarm_value"; // select column
$aresult = $con->query($query);
?>
<!DOCTYPE html>
<html>
<head>
<title>Massive Electronics</title>
<script ty...
Count Rows in Doctrine QueryBuilder
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Something like:
$qb = $entityManager->createQueryBuilder();
$qb->select('count(account.id)');
$qb->from('ZaysoCoreBundle:Account','account');
$count = $qb->getQuery()->getSingleScalarResult();
Some folks feel that expressions are somehow better than just using straight DQL. One...
Count work days between two dates
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For workdays, Monday to Friday, you can do it with a single SELECT, like this:
DECLARE @StartDate DATETIME
DECLARE @EndDate DATETIME
SET @StartDate = '2008/10/01'
SET @EndDate = '2008/10/31'
SELECT
(DATEDIFF(dd, @StartDate, @EndDate) + 1)
-(DATEDIFF(wk, @StartDate, @EndDate) *...
How to correct indentation in IntelliJ
...ode → Auto-Indent Lines (default Ctrl + Alt + I) for the current line or selection.
You can customise the settings for how code is auto-formatted under File → Settings → Editor → Code Style.
To ensure comments are also indented to the same level as the code, you can simply do as follows:...
Copy/duplicate database without using mysqldump
...the references, you can run the following to copy the data:
INSERT INTO x SELECT * FROM other_db.y;
If you're using MyISAM, you're better off to copy the table files; it'll be much faster. You should be able to do the same if you're using INNODB with per table table spaces.
If you do end up doin...
How to change package name of an Android Application
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Right-click on the package name (src/com.android.gesture.builder).
Select Refactor > Rename and change the name, for example to
com.android.gestureNEW.builder.
Open the manifest file. Inside the
<manifest> tag, change the package name to
com.android.gestureNEW.builder.
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