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Possible to do a MySQL foreign key to one of two possible tables?
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Well, i have two tables:
songs
a) Song number
b) Song title
....
playlists
a) Playlist number
b) Playlist title
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and i have an third
songs_to_playlist_relation
The problem is that some kinds of playlists have link to other playlists. But in mysql we don't have foreign...
CSS last-child selector: select last-element of specific class, not last child inside of parent?
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Here is a working example for you:
<!doctype html>
<head><title>CSS Test</title>
<style type="text/css">
.some-class { margin: 0; padding: 0 20px; list-style-type: square; }
.lfloat { float: left; display: block; }
.rfloat { float: right; display: block; }
/* apply st...
Rename MySQL database [duplicate]
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Bit easier to use version of this script: gist.github.com/tadas-s/5411299
– Tadas Sasnauskas
Apr 18 '13 at 8:59
1
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Javascript Confirm popup Yes, No button instead of OK and Cancel
Javascript Confirm popup, I want to show Yes, No button instead of OK and Cancel.
9 Answers
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How can I manipulate the strip text of facet_grid plots?
...trip text in facetted plots. My question
is similar to a question on plot titles , but I'm specifically concerned with
manipulating not the plot title but the text that appears in facet titles (strip_h).
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How to become an OpenCart guru? [closed]
...is->document->getTitle()- Get page title
$this->document->setDescription($description) - Set meta description
$this->document->getDescription()- Get meta description
$this->document->setKeywords()- Set meta keywords
$this->document->getKeywords()- Get meta keywords
$thi...
How to add a search box with icon to the navbar in Bootstrap 3?
...t" content="width=device-width, initial-scale=1">
<meta name="description" content="">
<meta name="author" content="">
<title>3 Col Portfolio - Start Bootstrap Template</title>
<!-- Bootstrap Core CSS -->
<link href="https://maxcdn.boo...
How to create a protocol with methods that are optional?
... to call it.
As an example, the pie chart view might test for the segment title method like this:
NSString *thisSegmentTitle;
if ([self.dataSource respondsToSelector:@selector(titleForSegmentAtIndex:)]) {
thisSegmentTitle = [self.dataSource titleForSegmentAtIndex:index];
}
The respondsToSele...
Changing font size and direction of axes text in ggplot2
... on the use of theme(). Here are common theme attributes for axis text and titles.
ggplot(mtcars, aes(x = factor(cyl), y = mpg))+
geom_point()+
theme(axis.text.x = element_text(color = "grey20", size = 20, angle = 90, hjust = .5, vjust = .5, face = "plain"),
axis.text.y = element_text(c...
Counting null and non-null values in a single query
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As i understood your query, You just run this script and get Total Null,Total NotNull rows,
select count(*) - count(a) as 'Null', count(a) as 'Not Null' from us;
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