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Select distinct using linq [duplicate]
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myList.GroupBy(test => test.id)
.Select(grp => grp.First());
Edit: as getting this IEnumerable<> into a List<> seems to be a mystery to many people, you can simply write:
var result = myList.GroupBy(test => test.id)
.S...
How to do INSERT into a table records extracted from another table
...UES", no parenthesis:
INSERT INTO Table2(LongIntColumn2, CurrencyColumn2)
SELECT LongIntColumn1, Avg(CurrencyColumn) as CurrencyColumn1 FROM Table1 GROUP BY LongIntColumn1;
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Linq Syntax - Selecting multiple columns
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.Where(x => x.EMAIL == givenInfo || x.USER_NAME == givenInfo)
.Select(x => new { x.EMAIL, x.ID });
AFAIK, the declarative LINQ syntax is converted to a method call chain similar to this when it is compiled.
UPDATE
If you want the entire object, then you just have to omit the call ...
How to get first and last day of previous month (with timestamp) in SQL Server
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select DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0) --First day of previous month
select DATEADD(MONTH, DATEDIFF(MONTH, -1, GETDATE())-1, -1) --Last Day of previous month
...
How to remove leading and trailing whitespace in a MySQL field?
...d the use case before using this solution:
trim does not work while doing select query
This works
select replace(name , ' ','') from test;
While this doesn't
select trim(name) from test;
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Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
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IF OBJECT_ID('tempdb..#FKs') IS NOT NULL
DROP TABLE #FKs
-- GET FKs
SELECT ROW_NUMBER() OVER (ORDER BY OBJECT_NAME(parent_object_id), clm1.name) as ID,
OBJECT_NAME(constraint_object_id) as ConstraintName,
OBJECT_NAME(parent_object_id) as TableName,
clm1.name as ColumnName...
How to avoid the “divide by zero” error in SQL?
...rder to avoid a "Division by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/"...
How to implement LIMIT with SQL Server?
...05, you can do this...
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 10 AND 20;
or something like this for 2000 ...
Best way to test SQL queries [closed]
...value, and all values are consecutive:
create view cm_absolute_month as
select *, year * 12 + month as absolute_month from month_value;
Now what we have to test is inherent in our spec, namely that for any tuple (year, month), there is one and only one (absolute_month), and that (absolute_month...
How to automatically select all text on focus in WPF TextBox?
If I call SelectAll from a GotFocus event handler, it doesn't work with the mouse - the selection disappears as soon as mouse is released.
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