Entity: usageType

Entity Type: Database table (platform schema)

Description: Platform-level catalogue of what measured consumption is used for (účel užití): heating, hot water, cooling, lighting, vehicle charging, irrigation … It replaces the compile-time union behind ConsumptionUsageType for gauge channels (the enum stays for buildingCalculatedConsumption). One catalogue for every tenant (decision R7, 1 Oct 2026 — tenant sub-items under other are a v2 candidate), maintained by the Porsenna superadmin; no tenantId, no RLS, the same precedent as platform.contract_item_type and distributionRate. Each item carries what the rest of the system needs from it: a category for grouping, the climate-normalisation method (Epic 3.2 normalises only hdd / cdd items), and the media × channel meanings it may be offered on (K1 matrix). A channel refers to it through gaugeUsageAllocationItem. Decided 1 Oct 2026 (R1–R7); the offer matrix (K1–K4) awaits stakeholder confirmation.

Data Attributes Table

Attribute Name	Description	Data Type	Default Value	Required (= Nullable)	Unique	Format	Validations	Index	Example
id	Primary key of the entity.	UUID	Generated in code (app layer)	Yes	Yes	UUID v7	-	Primary Key	01960000-0000-7000-8000-000000000701
code	Stable machine code.	String	-	Yes	Yes	lowerCamelCase — heating, hotWater, cooling, ventilation, lighting, baseLoad, cooking, evCharging, transport, sanitary, processWater, irrigation, other	Max 40 characters; unique among active rows.	name: idx_usageType_code, type: btree (unique, partial deletedAt IS NULL)	hotWater
nameCs	Czech label shown in the gauge form, the allocation modal and reports.	String	-	Yes	No	-	Max 100 characters; non-empty.	-	Ohřev teplé vody
labelByMedium	Optional medium-specific label (K2: a water meter shows Teplá voda for hotWater, an energy meter Ohřev teplé vody).	JSON (map medium → label)	null	No	No	{"water": "Teplá voda"}	Keys from enum Medium.	-	{"water": "Teplá voda"}
category	Grouping for reports and the modal: heat, technology, electric, fuel, water, production, other.	String	-	Yes	No	enum (fixed list above)	-	-	heat
normalizationMethod	How Epic 3.2 normalises consumption of this usage: none, hdd (heating degree days), cdd (cooling degree days).	String	none	Yes	No	enum	-	-	none
allowedFor	Which channels may carry this usage: list of (medium, purpose meaning) pairs — the K1 matrix as data, not two independent lists (N01).	JSON (array of {medium, purpose})	[]	Yes	No	[{"medium":"electricity","purpose":"consumption"}, …]	Non-empty for an active row; media from enum Medium, purposes from the gauge purpose meanings consumption / production / export. v1 lists consumption only (K3).	-	[{"medium":"gas","purpose":"consumption"},{"medium":"heat","purpose":"consumption"}]
sortOrder	Display order within the filtered offer (N10).	Integer	0	Yes	No	-	-	-	20
isActive	Whether the item is offered for new assignments. Deactivating keeps existing allocations readable (N09).	Boolean	true	Yes	No	-	-	-	true
em2Code	EM2 gauge_consumption_usage code the item migrates from (1 heating, 2 hot water, 5 other, 6 lighting, 7 other non-weather). Null for new items.	Integer	null	No	No	-	-	-	2
createdAt	Timestamp of creation. Immutable.	Timestamp with time zone	Set in code	Yes	No	ISO 8601	-	-	2026-10-05T10:00:00Z
updatedAt	Timestamp of last update.	Timestamp with time zone	Set in code	Yes	No	ISO 8601	-	-	2026-10-05T10:00:00Z
deletedAt	Soft-delete timestamp.	Timestamp with time zone	null	No	No	ISO 8601	-	-	null
createdBy	Actor who created the record.	String	-	Yes	No	type:actor	-	-	system:seed
updatedBy	Actor who last updated the record.	String	-	Yes	No	type:actor	-	-	system:seed

Notes

• Seed (v1, full set — decision R4): heating (HDD), hotWater, cooling (CDD), ventilation, lighting, baseLoad (Ostatní provoz — bez vlivu počasí), cooking, evCharging, transport, sanitary, processWater, irrigation, other. gridExport and sharing are not seeded as consumption usages — production, export and sharing stay outside the v1 split (K3) and are classified by the channel's purpose. No item is a default for any channel (D01): a new channel is Neurčeno until the user chooses.
• Offer per medium (K1, consumption channels): electricity — heating, hotWater, cooling, ventilation, lighting, baseLoad, cooking, evCharging, other · gas — heating, hotWater, cooking, other · heat — heating, hotWater, other · cold — cooling, other · water — sanitary, hotWater, processWater, irrigation, other · solid and liquid fuel — heating, hotWater, other · vehicle fuel — transport, other. KVP channels carry no usage.
• EM2 codes 3, 4, 8 (combi heating measured / combi coefficient / combi hot water measured) are not usages — they become the mode of gaugeUsageAllocation. EM2 code 0 migrates as no allocation (null), not as other, so the gap stays visible.
• Administration: superadmin read in v1 (same read-only pattern as the distribution-rate catalogue); the tenant reads GET /v1/usage-types?medium=&purpose= for the select and the modal; the backend validates every allocation against allowedFor (N10 — no second matrix in the frontend).