mysql - create treeview looping query -


i have designed treeview structure below: *parentid = 0 means tree root

id    parentid 1        0  2        0   3        1 4        1 5        1 6        3 7        4 8        5 9        5 10       5 11       2 12       2 13      10

when pass parameter of "1" return result of under root "1", expected result:

id  parentid 1        0 3        1 4        1 5        1 6        3 7        4 8        5 9        5 10       5 13      10

possible solve single query?

in way stored tree now, not possible entire tree in 1 pure sql query. need write loop in other language (c#, stored procedure supports loops, ...) fetch tree.

this nice article describing how work way of storing tree (including fetching tree , removing items tree).

even more interesting, article describes way store trees in database table does allow fetching entire tree in single query. it's called pre-order tree traversal. can more information. i've found c# implementation. involves more logic way using now, more performant smallest trees.


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