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

How Constraints Prevent Query Failures

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.