3.6 — Matching Retrieval to Data Shape and Query Pattern

CCAR-P Domain 3 · Task 3.6

What You Need to Know

Retrieval strategy rests on two axes: data shape and query pattern. Then name the failure that matters most and pick the cheapest strategy whose failure mode is acceptable.

Data Shape Axis

Shape	Native strategy
Live structured (DB, catalogues, accounts)	Query tool against system of record
Narrative documents (policies, manuals)	Semantic retrieval over chunked text
Code / rigid text	Structure-navigating retrieval
Small & stable	Cached prompt (no retrieval)

Query-Pattern Axis

Pattern	Cue	Native strategy
Exact lookup	Identifier (part #, error code)	Keyword / filtered search
Conceptual	“Summarise”, “what is our policy”	Semantic retrieval
Multi-hop / exploratory	Comparison, unknown path	Agentic retrieval
Recall-critical	“Must not miss a document”	Hybrid + reranking

Selection Method

1. Name the data shape
2. Name the query pattern
3. Name the failure that matters most
4. Pick the cheapest strategy whose failure mode is acceptable

One system can combine multiple strategies. Hybrid is a design answer, not a compromise.

Exam Traps

• Embedding live operational data into a vector store
• Applying one retrieval approach to every data shape
• Deploying agentic multi-hop on a simple latency-budgeted lookup
• Choosing precision/latency-first where no relevant document may be missed