Spring: How to use KeyHolder with PostgreSQL

Question

Recently migrated to POSTGRESQL, I am trying to obtain the uniquely generated key on creating a new entry into the db table. The table `screenstable` looks like this: ``` CREATE TABLE screenstable ( id serial NOT NULL, screenshot bytea, CONSTRAINT screen_id PRIMARY KEY (id ) ) ``` The method that inserts data into `screenstable` is as follows: ``` @Autowired NamedParameterJDBCTemplate template; public int insertImage(ImageBean imageBean){ String query = "insert into screenstable (screenshot) values (:image)"; SqlParameterSource data = new BeanPropertySqlParameterSource(imageBean); KeyHolder keyHolder = new GeneratedKeyHolder(); template.update(query, data, keyHolder); return keyHolder.getKey().intValue(); } ``` and `ImageBean` is ``` import java.util.Arrays; public class ImageBean { private int id; private byte[] image; @Override public String toString() { return "ImageBean [id=" + id + ", image=" + Arrays.toString(image) + "]"; } public int getId() { return id; } public void setId(in…

Accepted Answer

If the framework is not informed about which column is the key, it will return all columns of the table as keys.

You can inform it by passing a new parameter to the update method, as follows:

```
template.update(query, data, keyHolder, new String[] { "id" });
```

See NamedParameterJdbcTemplate.update(sql, paramSource, generatedKeyHolder, keyColumnNames)

Spring: How to use KeyHolder with PostgreSQL

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