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The SQL OVER() clause - when and why is it useful?
...ated values and then join it back to the original rowset, i.e. like this:
SELECT
orig.[Partition],
orig.Value,
orig.Value * 100.0 / agg.TotalValue AS ValuePercent
FROM OriginalRowset orig
INNER JOIN (
SELECT
[Partition],
SUM(Value) AS TotalValue
FROM OriginalRowset
G...
SQL to find the number of distinct values in a column
I can select all the distinct values in a column in the following ways:
11 Answers
11
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How to round an average to 2 decimal places in PostgreSQL?
... round that takes a precision is only available for numeric.
regress=> SELECT round( float8 '3.1415927', 2 );
ERROR: function round(double precision, integer) does not exist
regress=> \df *round*
List of functions
Schema | Name | Result data type | Argument...
How do I change an HTML selected option using JavaScript?
...
document.getElementById('personlist').getElementsByTagName('option')[11].selected = 'selected'
to
document.getElementById('personlist').value=Person_ID;
share
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What is the syntax for an inner join in LINQ to SQL?
...ke:
from t1 in db.Table1
join t2 in db.Table2 on t1.field equals t2.field
select new { t1.field2, t2.field3}
It would be nice to have sensible names and fields for your tables for a better example. :)
Update
I think for your query this might be more appropriate:
var dealercontacts = from conta...
Which method performs better: .Any() vs .Count() > 0?
...re generated SQLs. Beauties as you can see ;)
ANY:
exec sp_executesql N'SELECT TOP (1)
[Project2].[ContactId] AS [ContactId],
[Project2].[CompanyId] AS [CompanyId],
[Project2].[ContactName] AS [ContactName],
[Project2].[FullName] AS [FullName],
[Project2].[ContactStatusId] AS [ContactStatusI...
Row count with PDO
...
$sql = "SELECT count(*) FROM `table` WHERE foo = ?";
$result = $con->prepare($sql);
$result->execute([$bar]);
$number_of_rows = $result->fetchColumn();
Not the most elegant way to do it, plus it involves an extra query...
How do you create a read-only user in PostgreSQL?
I'd like to create a user in PostgreSQL that can only do SELECTs from a particular database. In MySQL the command would be:
...
Populating a razor dropdownlist from a List in MVC
...leaner separation.
First create a viewmodel to store the Id the user will select along with a list of items that will appear in the DropDown.
ViewModel:
public class UserRoleViewModel
{
// Display Attribute will appear in the Html.LabelFor
[Display(Name = "User Role")]
public int Sele...
- how to allow only one item selected?
I have a <SELECT multiple> field with multiple options and I want to allow it to have only one option selected at the same time but user can hold CTRL key and select more items at once.
...