SQL Server for Each Loop

SQL Server FOR EACH Loop

SQL is primarily a set-orientated language - it's generally a bad idea to use a loop in it.

In this case, a similar result could be achieved using a recursive CTE:

with cte as
(select 1 i union all
 select i+1 i from cte where i < 5)
select dateadd(d, i-1, '2010-01-01') from cte

How to write a foreach in SQL Server?

You seem to want to use a CURSOR. Though most of the times it's best to use a set based solution, there are some times where a CURSOR is the best solution. Without knowing more about your real problem, we can't help you more than that:

DECLARE @PractitionerId int

DECLARE MY_CURSOR CURSOR 
  LOCAL STATIC READ_ONLY FORWARD_ONLY
FOR 
SELECT DISTINCT PractitionerId 
FROM Practitioner

OPEN MY_CURSOR
FETCH NEXT FROM MY_CURSOR INTO @PractitionerId
WHILE @@FETCH_STATUS = 0
BEGIN 
    --Do something with Id here
    PRINT @PractitionerId
    FETCH NEXT FROM MY_CURSOR INTO @PractitionerId
END
CLOSE MY_CURSOR
DEALLOCATE MY_CURSOR

for each in MS SQL SERVER?

Use the following statement:

INSERT INTO EmployeePayroll
SELECT
  0,EmployeeID ,0,0,0
FROM
  Employees

You can check for the existance of the record before inserting it by appending:

WHERE
  ID NOT IN
  (
     SELECT
       EmployeeID
     FROM
       EmployeePayroll
  )

Syntax of for-loop in SQL Server

T-SQL doesn't have a FOR loop, it has a WHILE loop

WHILE (Transact-SQL)

WHILE Boolean_expression
BEGIN

END

What is the `name` property in the ForEach loop's ForEach File enumerator expressions?

In SSIS, the Name and Description properties are common for all SSIS tasks, components, containers, objects. Those properties are used as metadata for each SSIS object.

Regarding the ForEach Enumerator, it is an SSIS object that is embedded within the ForEach Loop Container. You can see this from the ForEach Loop Container property tab.

This means that the ForEach Enumerator object also has the Name and Description properties like any other SSIS object.

Test

I created a package, added a ForEach Loop Container. And change the enumerator type to ForEach File Enumerator. Then I assigned the following expression to the Name property: "aaa".

Now, in the Solution Explorer window, right click on the created package and click on View as Code.

We can check that the ForEach Enumerator object name is set to aaa.

ASP.NET MVC 5 / C# Foreach loop - repeats same data

There is a subtle problem with views when used from Entity Framework.

If you have a table, do use it with EF, you need to have a primary key to uniquely identify each row. Typically, that's a single column, e.g. an ID or something like that.

With a view, you don't have the concept of a "primary key" - the view just contains some columns from some tables.

So when EF maps a view, it cannot find a primary key - and therefore, it will use all non-nullable columns from the view as "substitute" primary key.

I don't know what these are in your case - you should be able to tell from the .edmx model.

So the problem really is that you can't have explicit primary keys on a view.

The easiest solution is to just simply include the primary key from both tables involved in your view definition (even if you don't want to show them ever).

That way, these will be in the view, and they will be non-nullable, and thus you should be fine and not getting any duplicates.

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