Insert Procedure with IF statement - sql

Question

I have procedure which i want to upgrade
it is inserting new record for client in pickup data table before insert it is checking if new record for this client was inserted this month if yes it not inserting new record
i am trying to update it so it will check if client StatusID in (1,2,6). So far i have this
alter PROCEDURE dbo.InsertPickup
#ClientID int, --Required ClientID and PickupDate
#PickupDate date
AS
IF NOT EXISTS (SELECT * FROM Pickup
WHERE ClientID = #ClientID
AND MONTH(PickupDate) = MONTH(#PickupDate)
AND YEAR(PickupDate) = YEAR(#PickupDate) )
if exists (select * from clients where statusid in (1,2,6))
INSERT INTO Pickup (ClientID, PickupDate)
VALUES (#ClientID, #PickupDate)
however it is not right it still inserting record if for example client with statusid = 5 or 3 or 4

Answer 1

You've not filtered your clients table by the #ClientID in your second IF EXISTS statement, hence it's not working as expected. Try:
if exists (select * from clients where statusid in (1,2,6) AND ClientID = #ClientID)

Answer 2

Proper indentation and BEGIN/END wrappers can go a long way toward spotting issues in queries. I've added the check to ClientID and also made your test against PickupDate sargable (in case there's an index now or will be one in the future).
IF NOT EXISTS
(
SELECT 1
FROM dbo.Pickup WHERE ClientID = #ClientID
AND PickupDate >= DATEADD(MONTH, DATEDIFF(MONTH, 0, #PickupDate), 0)
AND PickupDate < DATEADD(MONTH, DATEDIFF(MONTH, 0, #PickupDate)+1, 0)
)
BEGIN
IF EXISTS
(
SELECT 1
FROM dbo.clients WHERE ClientID = #ClientID
AND statusid IN (1,2,6)
)
BEGIN
INSERT INTO dbo.Pickup (ClientID, PickupDate)
VALUES (#ClientID, #PickupDate);
END
END
Of course you can also do this without all the nested IF tests:
INSERT dbo.Pickup(ClientID, PickupDate)
SELECT #ClientID, #PickupDate
WHERE EXISTS
(
SELECT 1 FROM dbo.clients WHERE ...
)
AND NOT EXISTS
(
SELECT 1 FROM dbo.Pickup WHERE ...
);