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DS-002: Data Model Design Specification

Property Value
ID DS-002
Version 1.0
Status Draft
Author
Approved By
Date

Purpose

This document describes the data model design for Essert.MF. Database schemas are documented in detail in the project's schema documentation and validated by the SchemaAnalyzerTool.

arc42 Cross-References

Design Aspect arc42 Section Key Content
Deployment topology 07 — Deployment View Database server configuration
Database contexts 05 s5.2.3 — Infrastructure 8 DbContexts, 175 tables
Connection management 08 s8.6 — Configuration Connection strings, pooling
Entity configuration 08 s8.12 — Mapping Patterns IEntityTypeConfiguration pattern

Database Overview

Database DbContext Tables Domain
db_process ProcessDataDbContext 1 Manufacturing processes
db_statistics StatisticsDbContext 23 Measurements, messages, cycle times
db_changelogs ChangelogsDbContext 70 Historical audit trail
db_essert EssertDbContext 3 System configuration
db_productparameter ProductParameterDbContext 63 Products, versions, parameters
db_robots RobotsDbContext 5 Robot master/position data
db_wpc WpcDbContext 4 Work piece carriers
db_systemparameter SystemParameterDbContext 8 System-level machine parameters

Total: 175 tables across 8 databases

ALCOA+ Compliance in Data Model

Every table follows the common column pattern (CC-05):

`UID` bigint(20) NOT NULL AUTO_INCREMENT,
`Timestamp` datetime DEFAULT NULL,
`Creator` varchar(30) DEFAULT NULL,
`CRC` bigint(20) DEFAULT NULL,
PRIMARY KEY (`UID`)

This ensures: - Attributable: Creator field identifies who created/modified the record - Legible: Structured data in typed columns - Contemporaneous: Timestamp records when the action occurred - Original: AUTO_INCREMENT UID ensures each record is unique and original - Accurate: CRC checksum detects unauthorized modifications

Schema Validation

The SchemaAnalyzerTool validates EF entity configurations against actual database schemas:

cd Essert.MF.SchemaAnalyzerTool
dotnet run
# Option 3: Comparison Report

This tool is used during IQ to verify schema alignment.

EF Core Configuration Pattern

All entities use IEntityTypeConfiguration<T>:

builder.ToTable("tbl_tablename");
builder.HasKey(e => e.Uid);
builder.Property(e => e.Uid).ValueGeneratedOnAdd();

See arc42/09 ADR-006 for the EF Core decision rationale.

Supporting Evidence