Graph-Focused Data Structures | Dataford Interview Questions

How would you solve a graph-focused data structure and algorithm problem end to end, including edge cases and complexity?

For this SQL exercise, treat the data as a directed graph and start traversal at node 1. Return the shortest reachable path to every node, while safely handling cycles and nodes that cannot be reached.

Output

One row per node, including the start node and unreachable nodes.
Columns: node_id, node_name, shortest_hops, and path.
Use NULL for unreachable nodes and order by node_id ascending.

Schema

graph_nodes

Column	Type	Description
node_idPK	INT	Unique graph node identifier
node_name	VARCHAR(100)	Display name for the node

graph_edges

Column	Type	Description
edge_idPK	INT	Unique directed edge identifier
from_node_id	INT	Source node of the directed edge
to_node_id	INT	Destination node of the directed edge

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