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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 you create a dropdownlist from an enum in ASP.NET MVC?
...pDownListFor
@Html.EnumDropDownListFor(
x => x.YourEnumField,
"Select My Type",
new { @class = "form-control" })
For MVC v5 use EnumHelper
@Html.DropDownList("MyType",
EnumHelper.GetSelectList(typeof(MyType)) ,
"Select My Type",
new { @class = "form-control" })
...
Locate current file in IntelliJ
...ecause you followed a reference to java.io.File.
The keymap defines it as Select current file or symbol in any view.
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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...
LINQ query to select top five
...
var list = (from t in ctn.Items
where t.DeliverySelection == true && t.Delivery.SentForDelivery == null
orderby t.Delivery.SubmissionDate
select t).Take(5);
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SQL RANK() versus ROW_NUMBER()
...he first 3 rows are tied when ordered by ID)
WITH T(StyleID, ID)
AS (SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,2)
SELECT *,
RANK() OVER(PARTITION BY StyleID ORDER BY ID) AS 'RANK',
ROW_NUMBER() OVER(PARTITION BY Style...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
Cannot simply use PostgreSQL table name (“relation does not exist”)
....
In other words, the following fails:
CREATE TABLE "SF_Bands" ( ... );
SELECT * FROM sf_bands; -- ERROR!
Use double-quotes to delimit identifiers so you can use the specific mixed-case spelling as the table is defined.
SELECT * FROM "SF_Bands";
Re your comment, you can add a schema to th...
How can I make SQL case sensitive string comparison on MySQL?
... @BT To make utf8 column case sensitive you could use bin colation like: SELECT 'email' COLLATE utf8_bin = 'Email'
– piotrekkr
Apr 23 '13 at 11:43
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Can I concatenate multiple MySQL rows into one field?
...
You can use GROUP_CONCAT:
SELECT person_id, GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT operator to avoid duplicates:
SELECT person_id, GROUP_CONCAT(DISTINCT ...