What This Field Means
The date from which the facts represented by this unit record are known to apply.
This is the first date on which the facts represented by the record or assertion are known to apply. It lets the site distinguish successive names, commands, locations, configurations, and statuses without collapsing them into one timeless description.
How to Read It Correctly
Effective From is not automatically the unit’s original activation or commissioning date. It can mark the beginning of a later designation, relationship, source-valid period, or record state.
Example
The effective date of a redesignation or documented organizational configuration.
Technical Specification
The database column is [USMIL-Unit].[Unit].[EffectiveFrom]. Optional date marking the beginning of the represented validity interval. It is not automatically the activation or commissioning date.
Store a calendar date only when the evidence supports the beginning of the represented interval. If only a year or approximate period is known, preserve that uncertainty in the evidence model rather than inventing a precise day.
| Property | Definition or current value |
|---|---|
| Database column | EffectiveFrom |
| Column order | 43 |
| SQL data type | date |
| Kind of information | Calendar date |
| Cardinality | One stored value per Unit row. |
| Required | No; NULL is permitted |
| Database default | No database default |
| Key or relationship | None |
| Database check constraint | ([CurrentStatus]=N'Planned' OR [CurrentStatus]=N'Status unknown' OR [CurrentStatus]=N'Historical' OR [CurrentStatus]=N'Inactive' OR [CurrentStatus]=N'Current') |
| Live population | 1230 of 9341 Unit records (13.17%) |
| Distinct nonblank values in the live table | 866 |
| Live profile measured | September 2, 2026, 20:43 UTC |
Allowed Values and Definitions
No preset menu applies to this field. It stores an identifier, relationship, measurement, date, timestamp, or evidence-derived narrative. Valid content is governed by the SQL type, key relationship, nullability, retained evidence, and the field-specific recording rule above. A list of observed contents would be data, not a list of allowed options.
Missing, Unknown, and Conflicting Information
A database NULL is permitted and means that no value is presently stored. It does not prove that the fact never existed, that the answer is no, or that the concept does not apply. Missing information must remain visibly different from a supported negative or inapplicable conclusion.
Connections to Other Fields
- Effective To — The date through which the represented facts are known to apply.
- Activation or Commission Date — The documented date the unit was activated or a ship or cutter command was commissioned.
- Current Status — Whether the unit is currently operating, belongs to history, was formally inactivated, is planned, or has an unresolved present status.
- Operational Context — The operation, campaign, exercise, contingency, or standing plan in which a command relationship or unit activity applies.
- Historical Command Alignment — The higher administrative or operational commands associated with the unit during a particular historical period.