Traversing directed cyclic graph in SQLite on Android

Question

Say I have two SQL tables: NODES and EDGES Nodes contains information pertaining to each node, and each row in EDGES contains a directed edge between two nodes.

ie

Table EDGES  
|edge_id | node_from_id | node_to_id |
|      1 |            1 |          2 |
|      2 |            1 |          3 |
|      3 |            2 |          1 |
|      4 |            3 |          5 |
|      5 |            6 |         10 |
|      6 |            6 |         11 |
|      7 |            7 |          8 |

Querying the table for all the children of a node is trivial, but what if I want to have a list of all the children of all the children of a node? Or better yet a list of all the edges that create a tree of the node's descendants? Note that the graph may be cyclical and is not fully connected.

For example, I want to select all the descendant edges of node 1:

QUERY Results:
|edge_id | node_from_id | node_to_id |
|      1 |            1 |          2 |
|      2 |            1 |          3 |
|      3 |            2 |          1 |
|      4 |            3 |          5 |

In SQL and SQLite 3.8.3+ I could use something like a Common Table Expression (CTE) to do this and there are many answers on SO to that effect. But on Android I'm currently limited to SQLite 3.4.0 which doesn't support CTE's.

I could programmatically query each level of the tree, but I would prefer to do this all in SQL if possible. Is there a neat way to accomplish this given my limitations?

Answer 1

CTEs exists because there is no other way to do recursive queries.

You have to query the children step by step.