A Brief Introduction to Graph Databases

Pitfalls in Graph Modeling

  • Dense nodes: Fan-out kills perf—split or index.
  • Wrong direction: Always specify -> or <-.
  • Over-properties: Keep lean; use nodes for complex.
  • No versioning: Model history with timed edges.

Explaining Dense Nodes in Depth

Nodes with thousands of edges slow traversals; split into sub-nodes.

Why avoid: Memory/per f issues.

Code Sample:

// Split dense
CREATE (hub:Hub) -[":PART_OF"]-> (sub:SubNode)

flowchart TD
Dense --> Sub1
Dense --> Sub2

Explaining Wrong Direction in Depth

Missing direction confuses semantics.

Why: Wrong query results.

Code Sample:

(a)-[":KNOWS"]->(b)  // Correct

flowchart LR
    A --> B

Explaining Over-Properties in Depth

Too many props per node bloats; use related nodes.

Why: Better organization.

Code Sample:

CREATE (p:Person)-[":HAS_ADDRESS"]->(addr:Address {street: '123 Main'})

flowchart TD
    P[Person] --> Addr[Address]

Explaining No Versioning in Depth

For history, use timed edges or version nodes.

Why: Track changes.

Code Sample:

CREATE (v1:Version {state: 'old'})-[":NEXT {time: '2025'}"]->(v2:Version {state: 'new'})

flowchart TD
    V1 -->|NEXT time=2025| V2

Test with load—simulate growth.

Why: Prevents perf hits.