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3rd chunk of `content/manuals/compose/how-tos/environment-variables/envvars-precedence.md`
edd6e582cea9a1ff69fb81c149209b436095b83c5091c19a0000000100000e24
|  8 |   -              |   -                             |   `VALUE`              |  `VALUE=1.5` |  `VALUE=1.4`            |  `VALUE=1.3`      ||**`VALUE=1.4`**  |
|  9 |   -              |   -                             |   `VALUE`              |  `VALUE=1.5` |   -                     |  `VALUE=1.3`      ||**`VALUE=1.3`**  |
| 10 |   -              |  `VALUE`                        |   -                    |  `VALUE=1.5` |  `VALUE=1.4`            |  `VALUE=1.3`      ||**`VALUE=1.4`**  |
| 11 |   -              |  `VALUE`                        |   -                    |  `VALUE=1.5` |  -                      |  `VALUE=1.3`      ||**`VALUE=1.3`**  |
| 12 |`--env VALUE`     |  `VALUE=1.7`                    |   -                    |  `VALUE=1.5` |  `VALUE=1.4`            |  `VALUE=1.3`      ||**`VALUE=1.4`**  |
| 13 |`--env VALUE=1.8` |  `VALUE=1.7`                    |   -                    |  `VALUE=1.5` |  `VALUE=1.4`            |  `VALUE=1.3`      ||**`VALUE=1.8`**  |
| 14 |`--env VALUE=1.8` |   -                             |  `VALUE=1.6`           |  `VALUE=1.5` |  `VALUE=1.4`            |  `VALUE=1.3`      ||**`VALUE=1.8`**  |
| 15 |`--env VALUE=1.8` |  `VALUE=1.7`                    |  `VALUE=1.6`           |  `VALUE=1.5` |  `VALUE=1.4`            |  `VALUE=1.3`      ||**`VALUE=1.8`**  |

### Result explanation

Result 1: The local environment takes precedence, but the Compose file is not set to replicate this inside the container, so no such variable is set.

Result 2: The `env_file` attribute in the Compose file defines an explicit value for `VALUE` so the container environment is set accordingly.

Result 3: The `environment` attribute in the Compose file defines an explicit value for `VALUE`, so the container environment is set accordingly.

Result 4: The image's `ENV` directive declares the variable `VALUE`, and since the Compose file is not set to override this value, this variable is defined by image

Result 5: The `docker compose run` command has the `--env` flag set which an explicit value, and overrides the value set by the image. 

Result 6: The `docker compose run` command has the `--env` flag set to replicate the value from the environment. Host OS value takes precedence and is replicated into the container's environment.

Result 7: The `docker compose run` command has the `--env` flag set to replicate the value from the environment. Value from `.env` file is selected to define the container's environment.

Result 8: The `env_file` attribute in the Compose file is set to replicate `VALUE` from the local environment. Host OS value takes precedence and is replicated into the container's environment.

Result 9: The `env_file` attribute in the Compose file is set to replicate `VALUE` from the local environment. Value from `.env` file is selected to define the container's environment.

Result 10: The `environment` attribute in the Compose file is set to replicate `VALUE` from the local environment. Host OS value takes precedence and is replicated into the container's environment.

Result 11: The `environment` attribute in the Compose file is set to replicate `VALUE` from the local environment. Value from `.env` file is selected to define the container's environment.

Result 12: The `--env` flag has higher precedence than the `environment` and `env_file` attributes and is to set to replicate `VALUE` from the local environment. Host OS value takes precedence and is replicated into the container's environment.

Results 13 to 15: The `--env` flag has higher precedence than the `environment` and `env_file` attributes and so sets the value.
Title: Docker Compose Environment Variable Resolution Examples and Result Explanation
Summary
This section provides examples and explanations for how Docker Compose resolves environment variables. It demonstrates the precedence order when setting environment variables using different methods such as `docker compose run` with `--env`, the `environment` attribute, the `env_file` attribute, image's `ENV`, host OS environment, and `.env` files. Each result is explained based on the precedence of these configurations.