Using Cursors On Select Statements In Procedures - Sybase Adaptive Server IQ 12.4.2 Administration And Performance Manual

Using cursors on SELECT statements in procedures

The following procedure uses a cursor on a SELECT statement. It illustrates
several features of the stored procedure language. It is based on the same query
used in the
ListCustomerValue
from procedures".
CREATE PROCEDURE TopCustomerValue
( OUT TopCompany CHAR(36),
OUT TopValue INT )
BEGIN
-- 1. Declare the "error not found" exception
DECLARE err_notfound
EXCEPTION FOR SQLSTATE '02000';
-- 2.Declare variables to hold
-- each company name and its value
DECLARE ThisName CHAR(36);
DECLARE ThisValue INT;
-- 3.Declare the cursor ThisCompany
-- for the query
DECLARE ThisCompany CURSOR FOR
SELECT company_name,
CAST( sum( sales_order_items.quantity *
AS value
FROM customer
INNER JOIN sales_order
INNER JOIN sales_order_items
INNER JOIN product
GROUP BY company_name;
-- 4. Initialize the values of TopValue
SET TopValue = 0;
-- 5. Open the cursor
OPEN ThisCompany;
-- 6. Loop over the rows of the query
CompanyLoop:
LOOP
FETCH NEXT ThisCompany
INTO ThisName, ThisValue;
IF SQLSTATE = err_notfound THEN
LEAVE CompanyLoop;
END IF;
IF ThisValue > TopValue THEN
SET TopCompany = ThisName;
SET TopValue = ThisValue;
END IF;
END LOOP CompanyLoop;
CHAPTER 6 Using Procedures and Batches
procedure described in "Returning result sets
product.unit_price ) AS INTEGER )
253