Why Does JPA Generate Tables with Columns in Alphabetical Order?

Incorrect Table Ordering in JPA-Generated Table

Problem:

Java Persistence API (JPA) seems to have generated a table with an incorrect column order, specifically with the 'name' column appearing before the 'organizationNumber' column, despite the desired ordering being the opposite.

Investigation:

Upon inspecting the table, the following ordering is observed:

+--------------------+--------------+------+-----+---------+----------------+
| Field              | Type         | Null | Key | Default | Extra          |
+--------------------+--------------+------+-----+---------+----------------+
| id                 | bigint(20)   | NO   | PRI | NULL    | auto_increment | 
| name               | varchar(255) | NO   |     | NULL    |                | 
| organizationNumber | varchar(255) | NO   | UNI | NULL    |                | 
+--------------------+--------------+------+-----+---------+----------------+

Cause:

JPA generates columns in alphabetical order by default. This ordering is intended to ensure deterministic ordering across clusters and avoid inconsistencies in column positions.

Workaround:

Unfortunately, there is no straightforward fix for this issue. One workaround is to manually name the columns in a way that forces the desired ordering. This can be achieved by prefixing the column names with appropriate alphanumeric characters, such as:

@Entity
@NamedQuery(name = "allOrganizations", query = "SELECT org FROM Organization org order by name")
public class Organization {

    private Long id;
    @Column(name = "a_name")
    private String name;
    @Column(name = "b_organizationNumber")
    private String organizationNumber;

    // ...
}

This approach will force the 'id' column to appear first, followed by 'name' (prefixed with 'a') and then 'organizationNumber' (prefixed with 'b').

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