Asgard EHS

Open-source compliance tools for EHS professionals. Local-first, single-binary Go applications that work standalone or as an integrated ecosystem.

---

Project maintained by asgardehs Hosted on GitHub Pages — Theme by mattgraham

Back to Odin docs

Schema Builder

The Schema Builder lets users design their own database tables, fields, and relationships from scratch — runtime DDL on SQLite with safety, auditability, and interoperability with pre-built modules.

Metadata Model

Three metadata tables describe user-defined schemas:

• _custom_tables — table definitions (name, display name, icon, establishment scope)
• _custom_fields — field definitions (name, type, required, default, type-specific config JSON)
• _custom_relations — relationships between tables (belongs_to, has_many, many_to_many; can target custom or pre-built tables)
• _custom_table_versions — DDL change history for each table

Field Types

Schema Builder Type	SQLite Type	Config Examples
text	TEXT	{"multiline": true, "max_length": 500}
number	INTEGER	{"min": 0, "max": 100}
decimal	REAL	{"precision": 2}
date	TEXT	stored as YYYY-MM-DD
datetime	TEXT	stored as ISO 8601
boolean	INTEGER	0/1
select	TEXT	{"options": ["Low", "Medium", "High"]}
relation	INTEGER	{"target_table": "cx_projects", "display_field": "name"}

Naming and Safety

All user-created tables get the cx_ prefix. The validator enforces:

• Table names: ^[a-z][a-z0-9_]{1,58}$ (after prefix, max 63 chars)
• Field names: ^[a-z][a-z0-9_]{1,62}$
• Reserved names blocked: id, establishment_id, created_at, updated_at (auto-added to every custom table)
• Cannot collide with pre-built table names
• Relation targets must exist

DDL Execution

The executor translates metadata into DDL:

Table creation adds id, establishment_id, created_at, updated_at automatically, plus an index on establishment_id.

Field addition uses ALTER TABLE ADD COLUMN.

Field deactivation sets is_active = 0 in metadata — hides from UI and query builder. SQLite column remains. Explicit compaction can drop it later (SQLite 3.35.0+).

Dynamic Query Builder

Safe parameterized queries for custom tables. Column names validated against metadata are interpolated; all data values are parameterized:

func (qb *QueryBuilder) Select(tableID int64, opts SelectOpts) (string, []any, error)
func (qb *QueryBuilder) Insert(tableID int64, values map[string]any) (string, []any, error)
func (qb *QueryBuilder) Update(tableID int64, id int64, values map[string]any) (string, []any, error)
func (qb *QueryBuilder) Delete(tableID int64, id int64) (string, []any, error)

Interoperability

Custom tables can relate to whitelisted pre-built tables:

• establishments, employees
• incidents, chemicals
• training_courses, training_completions
• storage_locations, work_areas

The query builder generates appropriate JOINs. RecordForm.svelte renders searchable dropdowns for relation fields.

Table Designer UI

1. Table metadata — display name, description, icon
2. Fields list — drag-to-reorder, type, required, config
3. Relations panel — source field, target table, relation type
4. Preview — live record form preview from current field definitions
5. Save — diffs against current state, executes necessary DDL

Schema Versioning

Every DDL change is recorded in _custom_table_versions — enables future undo, export, and schema sharing between establishments.