Loss DB schema

The modelled loss schema enables return period loss estimates and annual average loss to be stored and linked to a geographic unit. Loss datasets can be directly linked to the hazard, exposure, and vulnerability datasets which were used to create the modelled losses via fields in loss.model. The dataset also summarises the exposure and hazard types to which the losses relate, independent of those links.

Enumerated types provide consistent categories for referencing losses as: - Category: Buildings, Contents, Direct Damage to other Asset, or Business Interruption - Frequency: Return Period, Probability of exceedance, or Rate of exceedance - Loss type: Ground Up (economic) or Insured - Metric: Annual average loss, Annual average loss ratio, or Probable maximum loss.

Each model has any number of loss maps which in turn have any number of geospatially referenced loss values. The meta-data in the loss map table describes the type of losses, occupancy, return period, metric used and so on. Similarly, a model can also have any number of loss curve maps, with any number of geospatially referenced loss curve value arrays. The associated loss and loss curve values may optionally include an asset reference to link to elements from an exposure model.

ERD (modeled loss schema): loss table contents (violet) and links to common tables (yellow). The schema includes a SQL view (pink).

Table: loss.model

Each entry in this table represents a single loss model, describing the hazard and process, and data used to generate the losses.

Req	Field name	Type	Reference table	Description
*	id	INT		Unique number ID
*	name	VARCHAR	loss.model	Name of source model
	description	TEXT		Description of source model
	hazard_type	VARCHAR	hazard.hazard_type	2-digit code
	process_type	VARCHAR	hazard.process_type	3-digit code
	hazard_link	VARCHAR
	exposure_link	VARCHAR
	vulnerability_link	VARCHAR

Table: loss.map

Each entry in this table represents a collection of loss values with unit and loss type and metric, for a given occupancy type, return period and loss component (building, contents) produced by a loss model. Loss exceedance curves are contained elsewhere, in loss.curve_map.

Req	Field name	Type	Reference table	Description
*	id	INT		Unique number ID
*	loss_model_id	INT	loss.model	Unique number ID of source loss model
*	occupancy	cf_common.occupancy_enum		Destination of use of the asset
*	component	loss.component_enum		Type of affected component (e.g. buildings)
*	loss_type	loss.loss_type_enum		Type of loss (e.g. ground-up)
	return_period	INT		Number of return period in years
*	units	VARCHAR		Cost unit of measure
*	metric	loss.metric_enum		Type of loss metric (e.g. AAL)

Table: loss.map_values

Each entry in this table represents the loss value and location of the value, with the value relating to the information in loss.map.

Req	Field name	Type	Reference table	Description
*	id	BIGINT		Unique number ID
*	loss_map_id	INT	loss.map	Unique number ID of reference loss map
	asset_ref	VARCHAR		Alphanumeric code that identifies asset from exposure model
*	loss	FLOAT		Loss value in the unit specified in loss_map
*	the_geom	GEOM		Associated geometry

Table: loss.curve_map

Each entry in this table represents a collection of loss exceedance curves associated with the loss model. It describes the unit, type and metric of the loss, which is provided for a given occupancy type, and loss component (building, contents) produced by a loss model.

Req	Field name	Type	Reference table	Description
*	id	INT		Unique number ID
*	loss_model_id	INT	loss.model	Unique number ID of reference loss model
*	occupancy	cf_common.occupancy_enum		Destination of use of the asset
*	component	loss.component_enum		Component affected by loss
*	loss_type	loss.loss_type_enum		Type of loss
*	frequency	loss.frequency_enum		Frequency representation type
	investigation_time	INT		Investigation time in years (required if frequency is different from 'Return Period')
*	units	VARCHAR		Unit of measure of loss (e.g. USD, tons, etc)

Table: loss.curve_map_values

Each entry in this table provides the values for a loss esceedance curve and location to which the curve relates, with the value relating to the information in loss.curve_map.

Req	Field name	Type	Reference table	Description
*	id	BIGINT		Unique number ID
*	loss_curve_map_id	INT	loss.map	Unique number ID of reference loss curve map
	asset_ref	VARCHAR		Alphanumeric code that identifies asset from exposure model
*	losses	VARCHAR		Loss values in the unit specified in loss_curve_map
*	rates	FLOAT		Rate values associates with losses
*	the_geom	GEOM		Associated geometry

Types

Includes 4 types including the options for asset categories to which loss refers to, how the frequency is expressed, what is the metric in use and the types of losses.

ENUM name	Types	Description
Category_enum	Buildings Indicator Infrastructure Crops, livestock and forestry	Types of possible asset categories, consistent with the exposure schema. Indicators refers for example to population density or GDP; infrastructure refers for example to roads, or electricity grid.
frequency_enum	Rate of Exceedence Probability of Exceedence Return Period	How the frequency value reported in loss.curve_map is expressed.
metric_enum	AAL AALR PML	Type of loss metric used in loss.curve_map and loss.map Note: AAL = Annual Average Losses AALR = Average Annual Loss Ratio PML = Probable Maximal Loss (also known as Return Period Loss)
loss_type_enum	Ground Up Insured	Type of losses in loss.curve_map and loss.map.