* I have a first table `articles` where some data are missing.
* In the table `articles_tmp` I have a part of the missing data.
* So I want to UPATE `articles.path WHERE path IS NULL` with the data in `articles_tmp.path WHERE path IS NOT NULL`.

With **SQLite**, this doesn't works :

```
UPDATE articles 
SET path = (
      SELECT  at.path
      FROM articles_tmp AS at, articles AS a
      WHERE at.article_id = a.id AND a.path IS NULL AND NOT at.path IS NULL
)
WHERE path IS NULL

```

With MS Access, this works fine :

```
UPDATE  articles
    INNER JOIN  articles_tmp 
    ON  articles.id = articles_tmp.id 
SET  articles.path = articles_tmp.path
WHERE  articles.path IS NULL  AND  articles_tmp.path IS NOT NULL

```

Can someone help ?