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Boolean Field in Oracle
...r using Y and NULL as the values. This makes for a very small (read fast) index that takes very little space.
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SQL Server 2005 How Create a Unique Constraint?
...t to do it from a Database Diagram:
right-click on the table and select 'Indexes/Keys'
click the Add button to add a new index
enter the necessary info in the Properties on the right hand side:
the columns you want (click the ellipsis button to select)
set Is Unique to Yes
give it an appropriate...
Using LIMIT within GROUP BY to get N results per group?
...
For me something like
SUBSTRING_INDEX(group_concat(col_name order by desired_col_order_name), ',', N)
works perfectly. No complicated query.
for example: get top 1 for each group
SELECT
*
FROM
yourtable
WHERE
id IN (SELECT
S...
How to get the first five character of a String
...
You can use Substring(int startIndex, int length)
string result = str.Substring(0,5);
The substring starts at a specified character position and has a
specified length. This method does not modify the value of the current
instance. Instead, it re...
ExpressJS How to structure an application?
...err) {
// ...
}
main();
});
routes/
The routes directory has a index.js file. Its goal is to introduce a kind of magic to load all other files inside the routes/ directory. Here's the implementation:
/**
* This module loads dynamically all routes modules located in the routes/
* dire...
How to overlay images
...
<div class="container" style="position: relative">
<img style="z-index: 32; left: 8px; position: relative;" alt="bottom image" src="images/bottom-image.jpg">
<div style="z-index: 100; left: 72px; position: absolute; top: 39px">
<img alt="top image" src="images/top-image.jpg">...
How to correctly require a specific commit in Composer so that it would be available for dependent p
...have something to do with Composer prefering Packagist over GitHub specifically?
– Maciej Sz
Jan 23 '14 at 19:06
...
C# Iterate through Class properties
...
// the index of each item in fieldNames must correspond to
// the correct index in resultItems
var fieldnames = new []{"itemtype", "etc etc "};
for (int e = 0; e < fieldNames.Length - 1; e++)
{
newRecord
.GetType()
...
Alternative to iFrames with HTML5
... to be able to access via XMLHttpRequest(). The following is an example of PHP code you can include at the top of your page in order to send these headers to clients:
<?php
header('Access-Control-Allow-Origin: http://api.google.com');
header('Access-Control-Allow-Origin: http://some.example....
Facebook database design?
...s to make a composite primary key. A unique key, absolutely. The clustered index on that unique key, definitely. But I'd also put some sort of non-composite identity as the PK with a nonclustered index. That would allow other tables that need a "friend relationship ID" FK to easily tie to this table...