Stored procedure for insert update and delete - asp.net

Question

I am very new to stored procedures. I have a table with an Id auto increment. I want to insert, update and delete rows in my table.
What is wrong with my stored procedure?
CREATE PROCEDURE [dbo].[hrm_Languages]
(
#Name varchar(120),
#CreatedBy bigint=0,
#UpdatedBy bigint=0,
#IsDeleted bit=0
#ID int OUTPUT
)
AS
BEGIN
SELECT #ID = ISNULL(MAX(ID), 0) + 1
FROM [dbo].[Languages]
IF #StatementType = 'Insert'
BEGIN
insert into [dbo].[Languages] (Name, CreatedOn, UpdatedOn, CreatedBy, UpdatedBy, IsDeleted)
values(#Name, DateTime(), DateTime, #CreatedBy, #UpdatedBy, #IsDeleted)
SELECT #Name
WHERE NOT EXISTS (SELECT ID, NAME
FROM TableName
WHERE NAME = #Name)
BEGIN
END
END
IF #StatementType = 'Select'
BEGIN
select * from [dbo].[Languages]
END
IF #StatementType = 'Update'
BEGIN
UPDATE [dbo].[Languages]
SET Name = #Name, UpdateOn = DateTime()
WHERE ID = #ID
END
else IF #StatementType = 'Delete'
BEGIN
DELETE FROM [dbo].[Languages] WHERE ID = #ID
END
end
Getting these errors:
Msg 102, Level 15, State 1, Procedure hrm_Languages, Line 7
Incorrect syntax near '#ID'.
Msg 137, Level 15, State 1, Procedure hrm_Languages, Line 12
Must declare the scalar variable "#ID".
Msg 137, Level 15, State 2, Procedure hrm_Languages, Line 15
Must declare the scalar variable "#StatementType".
Msg 195, Level 15, State 10, Procedure hrm_Languages, Line 17
'DateTime' is not a recognized built-in function name.
Msg 156, Level 15, State 1, Procedure hrm_Languages, Line 24
Incorrect syntax near the keyword 'END'.
Msg 137, Level 15, State 2, Procedure hrm_Languages, Line 26
Must declare the scalar variable "#StatementType".
Msg 137, Level 15, State 2, Procedure hrm_Languages, Line 31
Must declare the scalar variable "#StatementType".
Msg 195, Level 15, State 10, Procedure hrm_Languages, Line 34
'DateTime' is not a recognized built-in function name.
Msg 137, Level 15, State 2, Procedure hrm_Languages, Line 38
Must declare the scalar variable "#StatementType".
Msg 137, Level 15, State 2, Procedure hrm_Languages, Line 40
Must declare the scalar variable "#ID".
I also want to show message on my web page using label that Name inserted, Nme deleted, NAme already exist

Answer 1

OK, problems with your sproc (after reading it again), please see comments:
-- If you worked for me, I'd be having words about this name, it does not state
-- what this sproc does.
CREATE PROCEDURE [dbo].[hrm_Languages]
(
#Name varchar(120),
#CreatedBy bigint=0,
#UpdatedBy bigint=0,
#IsDeleted bit=0, -- You need a comma here. You hadn't posted your errors when I answered
-- this site isn't really for fixing your compile errors... read
-- the error text, it's quite helpful. Something wrong on line 7...
#ID int OUTPUT
)
AS
BEGIN
-- Problem 1. You are selecting this ID prior to inserting. This won't always be the
-- ID inserted, if your system is getting heavy use.
SELECT #ID = ISNULL(MAX(ID), 0) + 1
FROM [dbo].[Languages]
-- Problem 2. You don't pass in #StatementType - this won't even compile.
IF #StatementType = 'Insert'
BEGIN
insert into [dbo].[Languages] (Name,CreatedOn,UpdatedOn,CreatedBy,UpdatedBy,IsDeleted)
values( #Name, DateTime(), DateTime, #CreatedBy, #UpdatedBy,#IsDeleted)
-- To get the inserted ID, do the following
SELECT #ID = SCOPE_IDENTITY()
-- Not sure what the following is for.
SELECT #Name
WHERE NOT EXISTS (SELECT ID,NAME FROM TableName
WHERE NAME=#Name)
BEGIN
END
END
-- This is where your sproc should end and the following should be three other sprocs.
IF #StatementType = 'Select'
BEGIN
select * from [dbo].[Languages]
END
-- Problem 3. You don't seem to be passing in and ID, just for output, and you set the ID in the
-- first line. If your system is heavily used, this might just end up updating a newly inserted
-- row, but most likely will update nothing.
-- Same goes for the delete below. Create separate sprocs for doing these things.
IF #StatementType = 'Update'
BEGIN
UPDATE [dbo].[Languages] SET
Name = #Name, UpdateOn= DateTime()
WHERE ID = #ID
END
else IF #StatementType = 'Delete'
BEGIN
DELETE FROM [dbo].[Languages] WHERE ID = #ID
END
end

Answer 2

In addition to the Paddy's Answer you must use GetDate() Instead of DateTime() to get the current DateTime.

Answer 3

I have corrected stored procedure syntactically. I have written comments for changes I have made. Correct sql will create SP for you.
CREATE PROCEDURE [dbo].[hrm_Languages]
(
#Name varchar(120),
#CreatedBy bigint=0,
#UpdatedBy bigint=0,
#IsDeleted bit=0, -- Insert comma
#StatementType Varchar(20), -- Add variable #StatementType
#ID int OUTPUT
)
AS
BEGIN
IF #StatementType = 'Insert'
BEGIN
-- As #ID will reset again after insertion of record so following two line are not needed
SELECT #ID = ISNULL(MAX(ID), 0) + 1
FROM [dbo].[Languages]
SELECT #Name
WHERE NOT EXISTS (SELECT ID,NAME FROM TableName -- What is table name for
WHERE NAME=#Name)
insert into [dbo].[Languages] (Name,CreatedOn,UpdatedOn,CreatedBy,UpdatedBy,IsDeleted)
values( #Name, SYSDATETIME(), SYSDATETIME(), #CreatedBy, #UpdatedBy,#IsDeleted)
-- SysDateTime is used to get current datetime
SELECT #ID = SCOPE_IDENTITY()
End
ELSE IF #StatementType = 'Select'
Begin
select * from [dbo].[Languages]
END
ELSE IF #StatementType = 'Update'
BEGIN
UPDATE [dbo].[Languages] SET
Name = #Name, UpdatedOn = SYSDATETIME()
WHERE ID = #ID
END
ELSE IF #StatementType = 'Delete'
BEGIN
DELETE FROM [dbo].[Languages] WHERE ID = #ID
END
END