What's wrong with my stored procedure shown here? [closed] - sql

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I'm trying to write a practice stored procedure query.
DELIMITER $$
CREATE PROCEDURE Select_All_Products_Ordered()
BEGIN $$
SELECT *
FROM northwind.Customers
ORDER BY CompanyName;
END $$
DELIMITER ;
It does not recognize the characters' first delimiter, the parentheses after Ordered(), the table name, nor the CompanyName.

Answer 1

Stored Procedure Declaration Syntax
T-SQL (the version of SQL used by SQL Server) does not declare stored procedure parameters with parenthesis. Instead it puts the parameter list between the procedure name and the keyword AS like this:
CREATE PROCEDURE Select_All_Products_Ordered
#myparameter int = 5
AS
-- ...
The procedure does not have to have any parameters, in which case the AS simply follows the procedure name. As such the parenthesis in your code should be replaced with the keyword AS.
DELIMITER
DELIMITER is not used in T-SQL.
This keyword is used in MySql (and possibly other databases) because they are unable to tell if the ; characters in the stored procedure body delimit the end of the the procedure or the end of one statements within the procedure. So to get around this the delimiter is redefined.
T-SQL in contrast will interpret everything from the AS keyword to the end of the batch as part of the stored procedure. As such it does not get confused by the ; characters and does not need to have the delimiter redefined.
The batch will normally run to the end of the file, however, most T-SQL editors will split a script up into batches to send to the server. This is normally done by splitting the script on the word GO at the start of a line. Note it is the editor that does this not SQL Server. Editors like SQL Server Management Studio (SSMS) can have this configured in the settings to a different pattern if you don't like GO. Also libraries like ADO.Net do not do this, so you have to split the script up yourself and send each batch via a separate server call.
BEGIN and END
BEGIN and END are only required if you wish to group a set of statements in to a block. This is useful for WHILE statements for example. As T-SQL treats everything from the AS keyword to the end of the batch as part of the stored procedure, there is no need for them here. That said it won't hurt if you want to leave them.
Missing Schema
Objects such as tables are grouped within SQL Server databases into Schemas. These each have a name, but the default one is dbo. You have used a multipart reference to the Customer table, however though you have given the database and table name you have not given the schema name. To specify the schema you put it between the database and server name like this northwind.dbo.Customers.
It is possible to leave out the schema name and SQL Server will use the default for the database, but in this case you need two dots like this northwind..Customers.
It is also possible to reference a table on a different server if a connection to the other server is registered with the one you are running on. In this case you would use a four part identifier ServerName.DatabaseName.SchemaName.TableName.
You can omit items from the start for the things the server is expected to know. So if you are connected to a particular database you can ommit the server name and database name. Also as mentioned the schema can be omitted and the default for the logged in user will be assumed.
Conclusion
So in order to get the stored procedure to run on SQL Server using a client tool like SQL Server Management Studio you would write it like this (I've included a call to the procedure at the end to show the batch separator, but this isn't required):
CREATE PROCEDURE Select_All_Products_Ordered
AS
SELECT *
FROM northwind.dbo.Customers
ORDER BY CompanyName;
GO
EXEC Select_All_Products_Ordered
GO
More detailed information about T-SQL's stored procedure syntax can be found on Microsoft's Docs site under CREATE PROCEDURE (Transact-SQL).