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Distinct in Linq based on only one field of the table
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Try this:
table1.GroupBy(x => x.Text).Select(x => x.FirstOrDefault());
This will group the table by Text and use the first row from each groups resulting in rows where Text is distinct.
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How to see the values of a table variable at debug time in T-SQL?
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DECLARE @v XML = (SELECT * FROM <tablename> FOR XML AUTO)
Insert the above statement at the point where you want to view the table's contents. The table's contents will be rendered as XML in the locals window, or you can add @v to the...
How do I UPDATE from a SELECT in SQL Server?
... SQL Server , it is possible to insert rows into a table with an INSERT.. SELECT statement:
35 Answers
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How does one reorder columns in a data frame?
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You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...
Select rows of a matrix that meet a condition
...20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will be a matrix in both cases.
If you want to use column names to select columns...
byte[] to hex string [duplicate]
...);
}
static string LinqConcat(byte[] data)
{
return string.Concat(data.Select(b => b.ToString("X2")).ToArray());
}
static string LinqJoin(byte[] data)
{
return string.Join("",
data.Select(
bin => bin.ToString("X2")
).ToArray());
}
static string LinqAgg(b...
postgresql - replace all instances of a string within text field
...g regex replacment. Let's see how easy it is to replace a cat with a dog.
SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat', 'dog');
--> Cat bobdog cat cats catfish
SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat', 'dog', 'i');
--> dog...
How do I search within an array of hashes by hash values in ruby?
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You're looking for Enumerable#select (also called find_all):
@fathers.select {|father| father["age"] > 35 }
# => [ { "age" => 40, "father" => "Bob" },
# { "age" => 50, "father" => "Batman" } ]
Per the documentation, it "returns a...
Android List Preferences: have summary as selected value?
...ile. How would I set the summary of the list activity to the value that is selected?
11 Answers
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Android: create a popup that has multiple selection options
... Hello, can you also show how I can set actions for specific item selections? Example: I want to let the user change the app language by clicking one of those items (probably using if statement).
– Arda Çebi
Feb 7 '18 at 20:11
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