Error: Query projections cannot include array, collection, or map fields

[Virag Kothari <vi...@yahoo-inc.com>]

Hi All,

I am facing the following exception when having a blob (byte[]) as part of select statement.

Caused by: <openjpa-2.2.2-r422266:1468616 nonfatal user error> org.apache.openjpa.persistence.ArgumentException: Query projections cannot include array, collection, or map fields.  Invalid query: "select  a.lob1 from DummyBean a"

The following are the relevant parts of DummyBean:


@NamedQuery(name = "GET_LOB1", query = "select  a.lob1 from DummyBean a"),


    @Column(name = "lob1")

    @Lob

    private byte[] lob1 = null;



Is there a way to selectively retrieve just the byte[] (blob) columns? I know that "select OBJECT(a) from …" would work.

Without using JPA, I can prepare the statement using java.sql.Statement and retrieve using ResultSet.getByteArray(). What should I do to make it work with JPA?


Appreciate any help.


Thanks,

Virag

Re: Error: Query projections cannot include array, collection, or map fields

[Virag Kothari <vi...@yahoo-inc.com>]

Hi All,

Has no one seen this issue with JPA?

Thanks,
Virag

On 7/30/13 12:46 PM, "Virag Kothari" <vi...@yahoo-inc.com> wrote:

>Hi All,
>
>I am facing the following exception when having a blob (byte[]) as part
>of select statement.
>
>Caused by: <openjpa-2.2.2-r422266:1468616 nonfatal user error>
>org.apache.openjpa.persistence.ArgumentException: Query projections
>cannot include array, collection, or map fields.  Invalid query: "select
>a.lob1 from DummyBean a"
>
>The following are the relevant parts of DummyBean:
>
>
>@NamedQuery(name = "GET_LOB1", query = "select  a.lob1 from DummyBean a"),
>
>
>    @Column(name = "lob1")
>
>    @Lob
>
>    private byte[] lob1 = null;
>
>
>
>Is there a way to selectively retrieve just the byte[] (blob) columns? I
>know that "select OBJECT(a) from Š" would work.
>
>Without using JPA, I can prepare the statement using java.sql.Statement
>and retrieve using ResultSet.getByteArray(). What should I do to make it
>work with JPA?
>
>
>Appreciate any help.
>
>
>Thanks,
>
>Virag
>
>
>
>
>
>
>