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How do I check if an index exists on a table field in MySQL?
...
Try:
SELECT * FROM information_schema.statistics
WHERE table_schema = [DATABASE NAME]
AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME]
It will tell you if there is an index of any kind on a certain column wi...
“A lambda expression with a statement body cannot be converted to an expression tree”
...SQL to be executed against the database.
Try this
Arr[] myArray = objects.Select(o => new Obj() {
Var1 = o.someVar,
Var2 = o.var2
}).ToArray();
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Difference between a theta join, equijoin and natural join
...ed SQL query would be like this (you can play with all the examples here)
SELECT *
FROM Product
JOIN Component
ON Product.Pname = Component.Pname
and the result:
| PNAME | PRICE | CNAME | COST |
----------------------------------
| Laptop | 1500 | CPU | 500 |
| Laptop | 1500 | hdd ...
Hidden Features of Xcode
...m working with a large or unfamiliar project.
To show the Favorites Bar, select the following menu option:
View > Layout > Show Favorites Bar
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edited Apr 4 '11...
jQuery: Select data attributes that aren't empty?
I'm trying to select all elements that have a data-go-to attribute that is not empty.
11 Answers
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How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...
Apache: client denied by server configuration
...fy any in this context? I'm asking because I was pulling my hair out here, and adding this it got everything working for me. The odd thing is the app was working with the existing vhost entry until a recent Apache upgrade to 2.4.9. Weirder again, is that it's working fine on another server with same...
Xcode 6 Bug: Unknown class in Interface Builder file
... this issue when using Xcode 6 beta 4.
To resolve this issue, you need to select each of your custom class objects in Storyboard (this includes any custom views, even the custom view controllers themselves).
Then with those objects selected, open the identity inspector and under "Custom Class" you...
What exactly does the .join() method do?
I'm pretty new to Python and am completely confused by .join() which I have read is the preferred method for concatenating strings.
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Android Studio with Google Play Services
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Go to File -> Project Structure
Select 'Project Settings'
Select 'Dependencies' Tab
Click '+' and select '1.Library Dependencies'
Search for : com.google.android.gms:play-services
Select the latest version and click 'OK'
Voila! No need to fight with Grad...