Java pgloader-如何将longblob作为oid导入？

简而言之

如何使用

pgloader

s.t.将

longblob

从MySQL迁移到Postgres。如果列被注释为

@Lob

和

@Basic（fetch=FetchType.LAZY）

，Hibernate会很高兴的

完整故事

所以我正在迁移（或者至少尝试）一个MySQL数据库到postgres。我现在正试图正确地移动这张桌子：

我当前的pgloader脚本相当简单：

LOAD DATABASE
    FROM      mysql://foo:bar@localhost:3306/foobar
    INTO postgresql://foo:bar@localhost:5432/foobar

    CAST
        type int to integer drop typemod,
        type bigint with extra auto_increment to bigserial drop typemod,
        type bigint to bigint drop typemod

    ALTER TABLE NAMES MATCHING 'User' RENAME TO 'users'
    ALTER TABLE NAMES MATCHING ~/./ SET SCHEMA 'public'
;

这足以加载数据并使外键工作

postgres表如下所示：

然而，

文件

是一个java实体，其内容被注释为

@Lob

：

@Entity
@Inheritance(strategy= InheritanceType.JOINED)
public class File extends BaseEntity {

    @NotNull
    private String name;

    @Column
    @Size(max = 4096)
    private String description;

    @NotNull
    private String mimeType;

    @Lob
    @Basic(fetch= FetchType.LAZY)
    private transient byte[] content;

    ...

}

这就是应用程序无法连接到迁移的数据库的原因，错误为：

Schema-validation: wrong column type encountered in column [content] in table [File];
                   found [bytea (Types#BINARY)], but expecting [oid (Types#BLOB)]

我如何让迁移工作正常进行

我确实试过设置

spring.jpa.properties.hibernate.jdbc.use_streams_for_binary=false

---

正如中所建议的，但这没有起任何作用。

嗯。。。我想我可以在事实发生后创建blob，正如

这意味着迁移脚本将获得扩展：

LOAD DATABASE
    FROM      mysql://foo:bar@localhost:3306/foobar
    INTO postgresql://foo:bar@localhost:5432/foobar

    CAST
        type int to integer drop typemod,
        type bigint with extra auto_increment to bigserial drop typemod,
        type bigint to bigint drop typemod

    ALTER TABLE NAMES MATCHING 'User' RENAME TO 'users'
    ALTER TABLE NAMES MATCHING ~/./ SET SCHEMA 'public'

    AFTER LOAD DO
        $$
            ALTER TABLE file RENAME COLUMN content TO content_bytes;
        $$,
        $$
            ALTER TABLE file ADD COLUMN content OID;
        $$,
        $$
            UPDATE file SET
                content = lo_from_bytea(0, content_bytes::bytea),
                content_bytes = NULL
            ;
        $$,
        $$
            ALTER TABLE file DROP COLUMN content_bytes
        $$
;

---

嗯。。。我想我可以在事实发生后创建blob，正如

这意味着迁移脚本将获得扩展：

LOAD DATABASE
    FROM      mysql://foo:bar@localhost:3306/foobar
    INTO postgresql://foo:bar@localhost:5432/foobar

    CAST
        type int to integer drop typemod,
        type bigint with extra auto_increment to bigserial drop typemod,
        type bigint to bigint drop typemod

    ALTER TABLE NAMES MATCHING 'User' RENAME TO 'users'
    ALTER TABLE NAMES MATCHING ~/./ SET SCHEMA 'public'

    AFTER LOAD DO
        $$
            ALTER TABLE file RENAME COLUMN content TO content_bytes;
        $$,
        $$
            ALTER TABLE file ADD COLUMN content OID;
        $$,
        $$
            UPDATE file SET
                content = lo_from_bytea(0, content_bytes::bytea),
                content_bytes = NULL
            ;
        $$,
        $$
            ALTER TABLE file DROP COLUMN content_bytes
        $$
;