The CREATE DBPROC statement defines a
database procedure.Syntax
<create_dbproc_statement> ::= CREATE DBPROC <procedure_name> [(<formal_parameter>,..)] AS <routine>
<formal_parameter> ::=
IN <argument> <data_type>
| OUT <argument> <data_type>
| INOUT <argument> <data_type>
<argument> ::= <identifier>
procedure_name, data_type, identifier, routineThe database procedure determines the average price for single rooms in hotels that are located within the specified zip code range.
CREATE DBPROC avg_price (IN zip CHAR(5), OUT avg_price FIXED(6,2)) AS
VAR total FIXED(10,2); price FIXED(6,2); hotels INTEGER;
TRY
SET total = 0; SET hotels = 0
SELECT price FROM tours.room,tours.hotel WHERE zip = :zip AND
room.hno = hotel.hno AND roomtype = ‘SINGLE‘;
WHILE $rc = 0 DO BEGIN
FETCH INTO :price;
SET total = total + price;
SET hotels = hotels + 1;
END;
CATCH
IF $rc <> 100 THEN STOP ($rc, ‘Unexpected error‘);
IF hotels > 0 THEN SET avg_price = total / hotels;
ELSE STOP (100, ‘No hotel found‘);
Explanation
A database procedure is a subroutine that runs on the SAP DB server. SAP DB provides a language (special SQL syntax that has been extended to include variables, control structures, and troubleshooting measures) that can be used to define database procedures and
triggers.The current user is the owner of a database procedure. He or she has the EXECUTE privilege to execute the procedure.
Parameter
When an application invokes the database procedure with the
CALL statement, it exchanges data via parameters that are defined by means of the formal parameters. A formal parameter of the database procedure usually corresponds to a variable in the application.IN | OUT | INOUT
The parameter mode (IN | OUT | INOUT) specifies the direction in which the data is transferred when the procedure is invoked.
IN: defines an input parameter, i.e. the value of the variable is transferred to the database procedure when the procedure is invoked.
OUT: defines an output parameter, i.e. the value of the formal parameter is transferred from the database procedure to the variable after the procedure has terminated.
INOUT: defines an input/output parameter that combines the IN and OUT functions.
Argument
By specifying an argument, you assign a name to a formal parameter of the database procedure. This parameter name can then be used as a variable in expressions and assignments in the database procedure.
Data Type
Only BOOLEAN, CHAR[ACTER], DATE, FIXED, FLOAT, INT[EGER], NUMBER, REAL, SMALLINT, TIME, TIMESTAMP, and VARCHAR can be used as the data type of a formal parameter of a database procedure.
Further information
routine