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Best way to check if object exists in Entity Framework?
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hi. how can we check if it exists and after that select all its data?
– virtouso
Apr 7 '15 at 1:27
1
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How to check if an element does NOT have a specific class?
...t one for the case in the question, but just as a reference if you need to select elements that don't have a certain class, you can use the not selector:
// select all divs that don't have class test
$( 'div' ).not( ".test" );
$( 'div:not(.test)' ); // <-- alternative
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How to select distinct rows in a datatable and store into an array
...n named ProcessName. This ProcessName contains repeated names.So i want to select only distinct names.Is this possible.
18 ...
How to select only the records with the highest date in LINQ
...is:
var q = from n in table
group n by n.AccountId into g
select new {AccountId = g.Key, Date = g.Max(t=>t.Date)};
If you want the whole record:
var q = from n in table
group n by n.AccountId into g
select g.OrderByDescending(t=>t.Date).FirstOrDefault();
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Remove rows with all or some NAs (missing values) in data.frame
...na.omit is nicer for just removing all NA's. complete.cases allows partial selection by including only certain columns of the dataframe:
> final[complete.cases(final[ , 5:6]),]
gene hsap mmul mmus rnor cfam
2 ENSG00000199674 0 2 2 2 2
4 ENSG00000207604 0 NA NA ...
Difference between decimal, float and double in .NET?
... | | | with 28 or 29 significant figures |
| char | System.Char | N/A | 2 | Any Unicode character (16 bit) |
| bool | System.Boolean | N/A | 1 / 2 | true or false |
+---------+----------------+-------...
Trigger change() event when setting 's value with val() function
... easiest and best way to trigger change event when setting the value of select element.
5 Answers
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What does “static” mean in C?
... an array type declaration as an argument to a function:
int someFunction(char arg[static 10])
{
...
}
In this context, this specifies that arguments passed to this function must be an array of type char with at least 10 elements in it. For more info see my question here.
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How to easily initialize a list of Tuples?
..." }, new Hold { Id = 2, Name = "You" } };
var anonymousProjections = holds.Select(x => new { SomeNewId = x.Id, SomeNewName = x.Name });
var namedTuples = holds.Select(x => (TupleId: x.Id, TupleName: x.Name));
Reuse the tuples later with grouping methods or use a method to construct the...
ALTER TABLE to add a composite primary key
...dexed from left to right.
For example, consider the following queries:
A) SELECT person, place, thing FROM provider WHERE person = 'foo' AND thing = 'bar';
B) SELECT person, place, thing FROM provider WHERE person = 'foo' AND place = 'baz';
C) SELECT person, place, thing FROM provider WHERE person ...