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linq query to return distinct field values from a list of objects
...f you just want the typeID values, it's easy - project to that with Select and then use the normal Distinct call.)
In MoreLINQ we have the DistinctBy operator which you could use:
var distinct = list.DistinctBy(x => x.typeID);
This only works for LINQ to Objects though.
You can use a groupin...
Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...e if there are no nulls in the DB, but will fail once nulls are inserted.
And you can always return the primitive type from the getter. Ex:
private Integer num;
public void setNum(Integer i) {
this.num = i;
}
public int getNum() {
return this.num;
}
But in most cases you will...
How do you join on the same table, twice, in mysql?
I have 2 tables. One (domains) has domain ids, and domain names (dom_id, dom_url).
3 Answers
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android.view.InflateException: Binary XML file: Error inflating class fragment
I have a very frustrating error that I cannot explain. I created an Android application that uses Android AppCompat to make it compatible with older versions. Here is my main activity layout file:
...
SQL left join vs multiple tables on FROM line?
...
The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER joins in ...
How to use Single TextWatcher for multiple EditTexts?
...
Can you please tell what is 'model' in above code and where to declare it?
– YuDroid
Jun 25 '12 at 6:56
33
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When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
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In Windows cmd, how do I prompt for user input and use the result in another command?
I have a Windows .bat file which I would like to accept user input and then use the results of that input as part of the call to additional commands.
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document.getElementById vs jQuery $()
...e same result as document.getElementById, you can access the jQuery Object and get the first element in the object (Remember JavaScript objects act similar to associative arrays).
var contents = $('#contents')[0]; //returns a HTML DOM Object
...
PostgreSQL - max number of parameters in “IN” clause?
..., but this is only
* possible if the inputs are all scalars (no RowExprs) and there is a
* suitable array type available. If not, we fall back to a boolean
* condition tree with multiple copies of the lefthand expression.
* Also, any IN-list items that contain Vars are handled as separate
* bo...