Constrained Oriented Query Language
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Translation Issue: Finite vs Limited
Prompt:
i have a problem with the translation of finite which can mean begrenzt or endlich or would only limited be "begrenzt"?
Answer:
- endlich = finite, something with a natural ending (e.g., finite set, lifespan).
- begrenzt = externally limited or constrained (e.g., limited resources).
- limited ≈ begrenzt; finite ≈ endlich.
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Difference between Limit and Constraint in Queries
Prompt:
limited on the other hand is too limited if you do a query with limit 2 you get 2. I would rather query constraint 2**64 to state how big an int can be and this is already done if you have a proper schema. You can also do a query countries constraint 250
Answer:
- LIMIT only restricts the output size at runtime.
- CONSTRAINT defines structural limits in schema (e.g., int max value, list size limit).
- Queries become safer and predictable when based on schema constraints, not runtime restrictions.
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Avoiding Horror Effects with Constraint-Based Queries
Prompt:
if we put this in a query language we can avoid horror effect like a * operator going rogue.
Answer:
- Constraint-enforced queries prevent uncontrolled resource consumption (* expansions, infinite loops).
- Embedding limits (max results, max depth, max data volume) ensures safe execution.
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Logical Principle
Explicit constraint > implicit behavior
Queries should not rely on database default behaviors; they must declare their safe operating parameters explicitly.
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Example: Constraint-Oriented Query
SELECT countries
WHERE population > 1_000_000
CONSTRAINT maxResults = 250
CONSTRAINT maxDepth = 3
CONSTRAINT maxDataVolume = 100MB
Notes:
- All resource-consuming aspects are bounded.
- No unbounded field expansion or uncontrolled depth.
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Problem-Solution Overview
| Problem | Solution |
|---|---|
| Rogue * expansion | Limit allowed fields via schema |
| Unlimited result sets | Explicit maxResults constraint |
| Infinite graph traversal | maxDepth constraint |
| Memory overload | maxDataVolume constraint |
| Infinite recursion | maxRecursionDepth constraint at schema level |
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Declarative Schema Constraint Example
entity Country {
name: String
population: Integer constraint (0..10^9)
}
entity Continent {
countries: List<Country> constraint (size 0..250)
}
Explanation:
- population must be between 0 and 10⁹.
- countries list cannot exceed 250 items.
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Summary
Embedding constraints in query languages and schema definitions ensures:
- No resource explosions
- Bounded query behavior
- Analyzable and predictable system performance
Avoiding "horror effects" becomes part of the system design — not an afterthought.