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Find most frequent value in SQL column
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SELECT `column`,
COUNT(`column`) AS `value_occurrence`
FROM `my_table`
GROUP BY `column`
ORDER BY `value_occurrence` DESC
LIMIT 1;
Replace column and my_table. Increase 1 if you wa...
What is the equivalent of 'describe table' in SQL Server?
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use Select * From INFORMATION_SCHEMA.COLUMNS Where TABLE_NAME = 'TABLENAME' if you don't want to use a stored procedure
– Matias Elorriaga
Aug 4 '14 at 18:21
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Effect of NOLOCK hint in SELECT statements
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1) Yes, a select with NOLOCK will complete faster than a normal select.
2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select.
Why would this be?
NOLOCK typically (...
How can I change IIS Express port for a site
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In Solution Explorer, right-click the name of the application and then select Properties.
Click the Web tab.
In the Servers section, under Use Local IIS Web server, in the Project URL box change the port number.
To the right of the Project URL box, click Create Virtual Directory, and then ...
How to select date without time in SQL
When I select date in SQL it is returned as 2011-02-25 21:17:33.933 . But I need only the Date part, that is 2011-02-25 . How can I do this?
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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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How do I wrap a selection with an HTML tag in Visual Studio?
...Studio 2015 comes with a new shortcut, Shift+Alt+W, that wraps the current selection with a div. This shortcut leaves the text "div" selected, making it seamlessly changeable to any desired tag. This coupled with the automatic end tag replacement makes for a quick solution.
UPDATE
This shortcut is a...
C#: How to convert a list of objects to a list of a single property of that object?
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List<string> firstNames = people.Select(person => person.FirstName).ToList();
And with sorting
List<string> orderedNames = people.Select(person => person.FirstName).OrderBy(name => name).ToList();
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How to declare a variable in a PostgreSQL query
...ows you to return a table of temporary values.
WITH master_user AS (
SELECT
login,
registration_date
FROM users
WHERE ...
)
SELECT *
FROM users
WHERE master_login = (SELECT login
FROM master_user)
AND (SELECT registration_date
FROM ma...
How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
...