insert only if entry does not exist?

[LucyP]

I feel like I should know how to do this, but:

I have to write some sql to add an entry to a table. I want the sql to check first that the entry does not exist though and I cannot get this to work.

This is the sql I've been using, but it doesn't work - can anyone tell me what I've missed (I think it's probably the way I've done the if statement - I learned this from a book only this morning)?

SELECT ListName
FROM ListNames
WHERE (ListName = 'SampleListName');
IF @@rowcount = 0
INSERT
INTO ListNames(ListName)
VALUES ('SampleListName')


thanks

 

[RickCole]

This should do what you want

IF (select count (Listname) from ListNames where ListName = 'SampleListName') = 0
begin
insert into ListNames(ListName)
values ('SampleListName')
end

Rick.

 

[marv76]

Or you could do this:

IF NOT EXISTS(SELECT ListName FROM ListNames WHERE ListName = 'SampleListName')
BEGIN
INSERT INTO ListNames(ListName)
VALUES('SampleListName')
END