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Is it a good idea to index datetime field in mysql?
I am working on designing a large database. In my application I will have many rows for example I currently have one table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
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ActiveRecord: List columns in table from console
...ething like Model.columns to get more info about the columns including database config data.
– srt32
Apr 21 '14 at 18:18
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Render partial from different folder (not shared)
... public NewViewEngine() {
// Keep existing locations in sync
base.PartialViewLocationFormats = base.PartialViewLocationFormats.Union(NEW_PARTIAL_VIEW_FORMATS).ToArray();
}
}
Then in your Global.asax.cs file, add the following line:
ViewEngines.Engines.Add(new NewViewEngine());
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Remove 'a' from legend when using aesthetics and geom_text
...1:8),]
p <- ggplot(d, aes(wt, mpg)) +
geom_point() +
theme_classic(base_size = 18) +
geom_label_repel(
aes(label = rownames(d), fill = factor(cyl)),
size = 5, color = "white"
)
# Let's see what the default legend looks like.
p
# Now let's override some of the aesthetics:
p +...
When and why are database joins expensive?
I'm doing some research into databases and I'm looking at some limitations of relational DBs.
7 Answers
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Why is super.super.method(); not allowed in Java?
...hin the same method) but not your parent's. For example, suppose we have a base "collection of items", a subclass representing "a collection of red items" and a subclass of that representing "a collection of big red items". It makes sense to have:
public class Items
{
public void add(Item item)...
Responsive css background images
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If you want the same image to scale based on the size of the browser window:
background-image:url('../images/bg.png');
background-repeat:no-repeat;
background-size:contain;
background-position:center;
Do not set width, height, or margins.
EDIT:
The previous...
How to add text inside the doughnut chart using Chart.js?
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None of the other answers resize the text based off the amount of text and the size of the doughnut. Here is a small script you can use to dynamically place any amount of text in the middle, and it will automatically resize it.
Example: http://jsfiddle.net/kdvuxbtj...
Web Service vs WCF Service
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This answer is based on an article that no longer exists:
Summary of article:
"Basically, WCF is a service layer that allows you to build applications that can communicate using a variety of communication mechanisms. With it, you can comm...
Why does ReSharper want to use 'var' for everything?
...use var for everything - I do lots and lots of code reviews using TFS (web based diffs) and it makes my job extremely difficult: i.e. var items = GetSomeItems(); vs IDataReader dr = GetSomeItems(); Missing using statement on both but easier for me to catch when using IDataReader vs var.
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