---
title: Code map loading
summary: Lazily loads and caches static in-memory code maps used throughout Unit Stat reporting, including three database-backed maps (offset type, cost type, calculation type) that silently drop unmatched database code values.
status: draft
owner: SAIF
last_reviewed: 2026-07-30
library: SAIF.Business.UnitStat
reference_type: package
operation_id: OP-US-06
trigger: Caller invokes any Get*Map function in mdlCodeMaps
---

# Code map loading

`mdlCodeMaps` centralizes lookup tables used to translate NCCI and internal codes into enumerated types across Unit Stat reporting. Most maps are pure in-memory constants; three ("extended" maps) load their code/description pairs from database code tables the first time they are requested, then cache the result for the life of the process.

| Field | Value |
| --- | --- |
| **Operation ID** | OP-US-06 |
| **Trigger** | Caller invokes any `Get*Map` function in `mdlCodeMaps` |
| **Inputs** | For the three database-backed maps: an `IDataPortalInfo` and an optional `refresh` flag; the other maps take no parameters |
| **Outputs** | A cached map object translating code values to strongly typed enumerations with descriptions |
| **Primary components** | `mdlCodeMaps.GetOffsetTypeMap`, `mdlCodeMaps.GetCostTypeMap`, `mdlCodeMaps.GetCalculationTypeMap`, and the constant in-memory `Get*Map` functions (RunType, ReportType, UpdateType, ReportRecordType, ReportCorrectionType, NCCIClaimStatusCode, NCCIInjuryCode, NCCIClaimTypes, NCCILossActTypes, NCCILossTypes, NCCIRecoveryTypes, NCCISettlementTypes, NCCIFraudulentClaimTypes, ExposureCoverageCode, ValuationMap) |
| **Entry point** | `Business\SAIF.Business.UnitStat\mdlCodeMaps.vb` |

## Steps

1. **In-memory maps.** Most `Get*Map` functions (RunType, ReportType, UpdateType, ReportRecordType, ReportCorrectionType, NCCIClaimStatusCode, NCCIInjuryCode, NCCIClaimTypes, NCCILossActTypes, NCCILossTypes, NCCIRecoveryTypes, NCCISettlementTypes, NCCIFraudulentClaimTypes, ExposureCoverageCode, ValuationMap) hold their code/enum/description entries as hard-coded constants inside a `Friend Sub New()` constructor; the first call to each function builds the map once into a `Static` local variable and every subsequent call in the same process returns the same cached instance. These maps have no database dependency.
2. **Database-backed map dispatch.** `GetOffsetTypeMap(dpi, refresh)`, `GetCostTypeMap(dpi, refresh)`, and `GetCalculationTypeMap(dpi, refresh)` each check a `Static` cache variable: if `refresh` is `True` or the cache is `Nothing`, a new map instance is constructed by querying its backing code table; otherwise the cached instance is returned immediately without any database access.
3. **Offset type map.** `clsOffsetTypeMap`'s constructor runs `SELECT code, code_descr FROM us_offset_type_code` ([SQL-019](../sql/SQL-019-us-offset-type-code-code-table-load.md), [US_OFFSET_TYPE_CODE](../database-tables.md#us-offset-type-code)) and maps each row's trimmed, upper-cased `code` value against a fixed `Select Case` (`FRDI`, `FRDP`, `FFRD`, `NDI`, `NDP`, `TPP`, `TPN`, `RFN`, `VOID`) to the corresponding `OffsetTypes` enum member.
4. **Cost type map.** `clsCostTypeMap`'s constructor runs `SELECT code, code_descr FROM us_cost_type_code` ([SQL-018](../sql/SQL-018-us-cost-type-code-code-table-load.md), [US_COST_TYPE_CODE](../database-tables.md#us-cost-type-code)) and maps `BOTH`, `INC`, `PAID`, `NONE` to the corresponding `CostTypes` enum member.
5. **Calculation type map.** `clsCalculationTypeMap`'s constructor runs `SELECT code, code_descr FROM calculation_type_code` ([SQL-017](../sql/SQL-017-calculation-type-code-code-table-load.md), [CALCULATION_TYPE_CODE](../database-tables.md#calculation-type-code)) and maps `ADD`, `SUB`, `MULT`, `DIV`, `MIN`, `MAX`, `NONE` to the corresponding `CalculationTypes` enum member.
6. **Unmatched codes are dropped.** In all three database-backed maps, a database row whose `code` value does not match any case in the `Select Case` block is simply skipped (the `Case` block has no `Case Else`), so an unrecognized or newly added database code value is silently excluded from the map rather than raising an error or a default/unknown enum entry.*
7. **Refresh is opt-in and per-process.** Because each map is cached in a `Static` variable local to its function, the cache is scoped to the application process/domain, not to any particular data-portal call; callers must explicitly pass `refresh:=True` to force a reload after the underlying code table changes, and even then only that single process's cache is refreshed.

## Process flow

```mermaid
flowchart TD
	Start([Caller invokes a Get_Map function]) --> Which{In-memory map or<br>database-backed map?}
	Which -->|In-memory| CachedA{Static cache<br>already built?}
	CachedA -->|Yes| ReturnA([Return cached constant map])
	CachedA -->|No| BuildA[Build map from<br>hard-coded constants]
	BuildA --> ReturnA
	Which -->|Database-backed| CachedB{refresh=True or<br>cache empty?}
	CachedB -->|No| ReturnB([Return cached map,<br>no DB access])
	CachedB -->|Yes| Query[Query backing code table:<br>US_OFFSET_TYPE_CODE,<br>US_COST_TYPE_CODE, or<br>CALCULATION_TYPE_CODE]
	Query --> MatchLoop{For each row,<br>code matches a<br>known Case?}
	MatchLoop -->|Yes| AddEntry[Add code to enum<br>mapping with description]
	MatchLoop -->|No| Drop([Row silently dropped])
	AddEntry --> CacheB[Cache built map]
	Drop --> CacheB
	CacheB --> ReturnB
```

## Failure and edge-case behavior

- Any code value present in `US_OFFSET_TYPE_CODE`, `US_COST_TYPE_CODE`, or `CALCULATION_TYPE_CODE` that does not match one of the hard-coded `Case` values is silently excluded from its map, with no logging, error, or fallback "unknown" entry — a new or renamed database code requires a corresponding code change in `mdlCodeMaps.vb` to be usable.*
- The three database-backed maps are cached per process via `Static` variables; a `refresh:=True` call only affects the calling process's cache, so multi-process deployments may see stale maps until each process independently refreshes or restarts.*
- The in-memory maps have no database dependency at all and cannot become stale relative to a database code table, but conversely cannot pick up new codes without a code change and redeploy.

## Related documentation

- [Operations and processes](../operations-processes.md)
- [Business rules](../business-rules.md)
- [SQL catalog](../sql/index.md)
- [Database tables](../database-tables.md)

> **Note:** Statements marked with `*` were inferred from code structure, naming conventions, or
> contextual evidence where direct confirmation was not available in source artifacts. Statements
> marked with `**` could not be confirmed; treat as unknown until verified.

## Sources

- `Business\SAIF.Business.UnitStat\mdlCodeMaps.vb`