I am working with TSP(Traveling salesmen problem) Solution in mysql.
for that we are going to develop procedure where i want to execute following query
-- variable coming from java
CREATE PROCEDURE solve_tsp(
inout ids varchar(21845);
)
begin
declare ret_ids varchar(21845);
-- some code
while length(ids) > 0 do
-- some assignment
SELECT to_id,distance into @l_tmp_id,@l_distance FROM mst_distance_matrix WHERE from_id =',@l_tmp_id,' AND
to_id IN (ids) -- ids is variable contains comma delimited string.
order by distance desc limit 1
-- concat value of to_id in ret_ids variable and then remove from ids variable
end while;
select ret_ids;
end;
You should look here.
http://dev.mysql.com/doc/refman/5.0/en/sql-syntax-prepared-statements.html
Example:
PREPARE stmt1 FROM 'SELECT SQRT(POW(?,2) + POW(?,2)) AS hypotenuse';
SET @a = 3;
SET @b = 4;
EXECUTE stmt1 USING @a, @b;
DEALLOCATE PREPARE stmt1;
See also: