Creates a new procedure in the database in a manner compatible with Adaptive Server Enterprise.
The following subset of the Transact-SQL CREATE PROCEDURE statement is supported in SQL Anywhere.
CREATE [ OR REPLACE ]PROCEDURE [owner.]procedure_name [ NO RESULT SET ] [ [ ( ] @parameter-name data-type [ = default ] [ OUTPUT ], ... [ ) ] ] [ WITH RECOMPILE ] AS statement-list
OR REPLACE clause Specifying OR REPLACE creates a new procedure, or replaces an existing procedure with the same name. This clause changes the definition of the procedure, but preserves existing permissions. An error is returned if you attempt to replace a procedure that is already in use.
WITH RECOMPILE clause This clause is accepted for Transact-SQL compatibility, but is ignored. SQL Anywhere always recompiles procedures the first time they are executed after a database is started, and stores the compiled procedure until the database is stopped.
The following differences between Transact-SQL and SQL Anywhere statements (Watcom SQL) are listed to help those writing in both dialects.
Variable names prefixed by @ The @ sign denotes a Transact-SQL variable name, while Watcom SQL variables can be any valid identifier, and the @ prefix is optional.
Input and output parameters Watcom SQL procedure parameters are INOUT by default or can be specified as IN, OUT, or INOUT. Transact-SQL procedure parameters are INPUT parameters by default. They can be specified as input/output with the addition of the OUTPUT keyword. There are no output-only parameters in the Transact-SQL dialect.
When you use the Watcom SQL dialect to declare a parameter OUT, it is output-only. The mixing of dialects is not recommended because it can cause problems when the procedure declaration is unloaded and used to rebuild the database. If the procedure declaration is unloaded and used to rebuild the database, the rebuilt procedure declaration is in the Transact-SQL dialect, the OUTPUT keyword is used, and the parameter is input/output.
Parameter default values Watcom SQL procedure parameters are given a default value using the keyword DEFAULT, while Transact-SQL uses an equality sign (=) to provide the default value.
Returning result sets Watcom SQL uses a RESULT clause to specify returned result sets. In Transact-SQL procedures, the column names or alias names of the first query are returned to the calling environment.
The following Transact-SQL procedure illustrates how result sets are returned from Transact-SQL stored procedures:
CREATE PROCEDURE showdept @deptname varchar(30) AS SELECT Employees.Surname, Employees.GivenName FROM Departments, Employees WHERE Departments.DepartmentName = @deptname AND Departments.DepartmentID = Employees.DepartmentID;
The following is the corresponding Watcom SQL procedure:
CREATE PROCEDURE showdept(in deptname varchar(30) ) RESULT ( lastname char(20), firstname char(20)) ON EXCEPTION RESUME BEGIN SELECT Employees.Surname, Employees.GivenName FROM Departments, Employees WHERE Departments.DepartmentName = deptname AND Departments.DepartmentID = Employees.DepartmentID END;
Procedure body The body of a Transact-SQL procedure is a list of Transact-SQL statements prefixed by the AS keyword. The body of a Watcom SQL procedure is a compound statement, bracketed by BEGIN and END keywords.
Must have RESOURCE authority.
SQL/2008 Transact-SQL extension.
Transact-SQL SQL Anywhere supports a subset of the Adaptive Server Enterprise CREATE PROCEDURE statement syntax.
Only Transact-SQL SQL procedures are supported in the SQL Anywhere Transact-SQL dialect. To create an external procedure you must use Watcom SQL syntax. Adaptive Server Enterprise does not support the NO RESULT SET clause. If the Transact-SQL WITH RECOMPILE optional clause is supplied, it is ignored. SQL Anywhere always recompiles procedures the first time they are executed after a database is started, and stores the compiled procedure until the database is stopped.
Groups of Transact-SQL procedures are not supported in SQL Anywhere.
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