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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
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Suppose I have the following table T:
a b
--------
1 abc
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But wha...
SQL Server SELECT LAST N Rows
...Feature also. A great example can be found here:
I am using the Orders table of the Northwind database... Now let us retrieve the Last 5 orders placed by Employee 5:
SELECT ORDERID, CUSTOMERID, OrderDate
FROM
(
SELECT ROW_NUMBER() OVER (PARTITION BY EmployeeID ORDER BY OrderDate DESC) AS Or...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
I have a contacts table which contains fields such as postcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way becaus...
SQL update from one Table to another based on a ID match
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You might want to use the table alias in the UPDATE clause, otherwise it will cause problems if you self join the table at any point.
– Tom H
Oct 22 '08 at 20:38
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MongoDB Many-to-Many Association
...y relationship)? Even the MongoDB docs hint that you should avoid having mutable, huge arrays of references. docs.mongodb.org/manual/tutorial/…
– CaptSaltyJack
Feb 1 '15 at 20:07
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Frequency table for a single variable
One last newbie pandas question for the day: How do I generate a table for a single Series?
4 Answers
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How to get sp_executesql result into a variable?
...LARE @sSQL nvarchar(500);
DECLARE @ParmDefinition nvarchar(500);
DECLARE @tablename nvarchar(50)
SELECT @tablename = N'products'
SELECT @sSQL = N'SELECT @retvalOUT = MAX(ID) FROM ' + @tablename;
SET @ParmDefinition = N'@retvalOUT int OUTPUT';
EXEC sp_executesql @sSQL, @ParmDefinition, @retv...
UPDATE and REPLACE part of a string
I've got a table with two columns, ID and Value . I want to change a part of some strings in the second column.
9 Answer...
Good way to use table alias in Update statement?
I'm using SQL Server, and trying to update rows from within the same table. I want to use a table alias for readability.
2 ...
Printing object properties in Powershell
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Try this:
Write-Host ($obj | Format-Table | Out-String)
or
Write-Host ($obj | Format-List | Out-String)
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