File unq

File Extension: .unq (Unique & Dictionary Index)

Turkce Dokumantasyon | English Documentation

Category: Physical File Formats
Subsystem: Indexing & Uniqueness Subsystem (AmberDB::Index)
Entry Type: Authoritative Storage File Format

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1. Definition and Overview

The .unq (Unique & Dictionary Index) file is an authoritative bidirectional dictionary table (dbstore/tables/${table}_${block}.unq) that simultaneously enforces field uniqueness constraints (valid => "unique") and transparently maps textual attribute labels (e.g. Brands, Publishers, Variant names) to compact integer identifiers.

AmberDB standardizes on .unq (superseding legacy .str) to prevent confusion with .srt (Sort indexes) and unify uniqueness enforcement.

.unq Bidirectional Key Mapping Architecture

 1. String to ID:  s:Penguin Books  ──>  10
 2. ID to String:  n:10             ──>  Penguin Books
 3. Auto Last ID:  lastid           ──>  10

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2. Core Mechanics

1. Uniqueness Enforcement (valid => "unique"):
   • For unique attributes (such as emails, usernames, SKUs, or barcodes), the engine checks s:$value in the .unq index during insert_id and modify_id.
   • Conflicts immediately raise validation errors.
2. Relational String Resolution (rdbm):
   • When text labels are supplied for relational fields or facet filters, the engine resolves or registers dictionary IDs via .unq lookups.

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3. See Also & Related Topics

• Concept: Relational Records
• Concept: File Structure
• File: .fac (Facet Index)
• Method: facet_menu