Question

I have a SPROC let’s call it: AccountExists, with parameter AccountID. I have another SPROC let’s call this one: CreateAccount.

I want to call the AccountExists from the CreateAccount, and pass the AccountID along. Sort of like this:

IF NOT EXISTS (AccountExists(AccountID))
BEGIN
     INSERT INTO dbo.Accounts
         (AccountID,
          AccountName)
END

If you are able to follow the logic I want a create account SPROC that will call the check to see if the account already exists.

Answer 1

I’m not sure if I understood your question correctly, but I’ll try to post the answer.

The first example here uses the stored procedure with the output parameter will return the result into the boolean variable @AccountExists what is as you can see quite overkill.

CREATE PROCEDURE AccountExists
  @AccountID INT,
  @AccountExists BIT OUTPUT
AS
BEGIN
  IF NOT EXISTS (SELECT * FROM dbo.Accounts WHERE AccountID = @AccountID)
    SET @AccountExists = 0
  ELSE
    SET @AccountExists = 1
END

CREATE PROCEDURE CreateAccount
  @AccountID INT
AS
BEGIN
  DECLARE @AccountExists BIT
  EXEC AccountExists @AccountID, @AccountExists OUT

  IF NOT @AccountExists
    INSERT INTO dbo.Accounts (AccountID, AccountName) VALUES ...    
END

The second example uses user defined function what is IMHO what you have tried to iplie in your question.

CREATE FUNCTION AccountExists
  (@AccountID INT)
RETURNS BIT
AS
BEGIN
  IF NOT EXISTS (SELECT * FROM dbo.Accounts WHERE AccountID = @AccountID)
    RETURN 0
  ELSE
    RETURN 1
END

CREATE PROCEDURE CreateAccount
  @AccountID INT
AS
BEGIN      
  IF SELECT AccountExists(@AccountID) = 0
    INSERT INTO dbo.Accounts (AccountID, AccountName) VALUES ...    
END

And finally the third example uses simple inlined test for value existence. I don’t know how complicated (and how frequent in your code) will your account existence verification be, so this way might be uncomfortable for you a bit.

CREATE PROCEDURE CreateAccount
  @AccountID INT
AS
BEGIN      
  IF NOT EXISTS (SELECT * FROM dbo.Accounts WHERE AccountID = @AccountID)
    INSERT INTO dbo.Accounts (AccountID, AccountName) VALUES ...    
END

I’m not sure if that’s what you were looking for. Also please note that it’s quite a long time I’ve worked with TSQL, so if it’s wrong then beat me up 🙂