Question

I am creating a trigger on a table in a SQL Server database.

But what I am unable to do is this: I have variables @pageid and @templateid populated, and I need to read all template column id’s from one table – basically get a list of them (they depend on the template id and can vary in number) so I need some way of making an array or something and go through it and add it to a table.

So…

1. how do I read all template id’s (image below: from 1st table (available template fields) – where availabletemplateid is @templateid) into an array?

2. how do I loop through this array and add them one by one it to another table (image below: 2nd table – (public page to field mapping) with publicpageid = @pageid and fieldid is one by one from the previous step, and field content is “-“)

So far I have

ALTER TRIGGER CreatePageFields
ON dbo.PublicPages
FOR INSERT
AS
BEGIN TRANSACTION

/* variables */
DECLARE
    @pageid bigint,
    @templateid bigint

/* insert template fields for this page */
SELECT @pageid = id, @templateid = templateid FROM inserted

/* TODO 1 get all template field id's */
/* TODO 2 insert each templatefieldid / page combination */    

/* execute */
COMMIT TRANSACTION

GO

Thanks a lot

Answer 1

I don’t think you need an array (table variable) or any looping (cursor). Something like this will be much, much faster (guessing at your table and field names):

INSERT INTO publicpagetofieldmapping (PublicPageID, FieldID, FieldContent)
SELECT t1.ID, t2.ID, '-'
FROM INSERTED t1
JOIN AvailableTemplateFields t2
ON t1.TemplateID = t2.availabletemplateid