> For the complete documentation index, see [llms.txt](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/7.19.1/mapping-sets/mapping-set-transformations/populate-mapping-set-targets.md).

# Populate Mapping Set Targets

This feature allows mappings without target codes in a Mapping Set (*target*) to be populated based on mappings from another Mapping Set (*source*). Only completed mappings (with targets) from the source Mapping Set are considered as a basis for copying targets to the target Mapping Set for mappings with the same source but without target codes. For example:

| **Source Mapping Set** | **Target Mapping Set before** | **Target Mapping Set after**              |
| ---------------------- | ----------------------------- | ----------------------------------------- |
| A → 1                  | A →                           | A → 1 (mapping found in source)           |
| B → 2                  | B →                           | B → 2 (the first mapping found in source) |
| B → 3                  |                               | B → 3 (an additional member is created)   |
| C →                    | C →                           | C → (no mapping found in source)          |
| D → 4                  | D → 5                         | D → 5 (already mapped, original is kept)  |

To invoke this feature, go to `Tools > Copy Mapping Set targets...` in the main menu or right-click on a Mapping Set to reveal the same menu item in the Context Menu.

![](https://snowowl.atlassian.net/wiki/download/thumbnails/1377828902/image2020-12-11_17-17-31.png?version=1\&modificationDate=1607703453614\&cacheVersion=1\&api=v2\&height=250)

![Populate Mapping Set Targets menus](https://snowowl.atlassian.net/wiki/download/thumbnails/1377828902/image2020-12-11_17-19-21.png?version=1\&modificationDate=1607703563297\&cacheVersion=1\&api=v2\&height=250)

The menu opens a wizard where the *Source* and the *Destination* Mapping Sets can be selected from a pick-list. In addition, comments can be copied from the source Mapping Set to the destination Mapping Set by ticking the **`Copy comments from source Mapping Set`** checkbox.

![Populate Mapping Set Target Values Wizard](https://snowowl.atlassian.net/wiki/download/attachments/1377828902/image2021-3-19_15-31-53.png?version=1\&modificationDate=1616164315328\&cacheVersion=1\&api=v2)