[OPENJPA-740] In MySQL use LONGBLOB, MEDIUMBLOB etc.. when needed, cause BLOB only holds 64kb of data.

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.2.0, 1.2.1, 1.2.2, 1.3.0, 2.0.0-M3, 2.0.0-beta, 2.0.0-beta2
• Fix Version/s: 1.3.0, 2.0.0-beta3
• Component/s: sql
• Patch Info: Patch Available
• Assignee: Donald Woods
• Reporter: Simone Gianni
• Created: 07/Oct/08 22:15
• Updated: 03/Nov/10 16:02
• Resolved: 08/Mar/10 21:50

Description

When a column is annotated as a BLOB of using @Persistent to use streaming blobs, and the underlying database is MySQL, OpenJPA will create a column of type BLOB. Unfortunately, in MySQL a BLOB column can hold a (vary) limited amount of data, while (especially when using streaming blobs) the user would probably expect it to hold a large amount of data.

Also adding the @Column annotation and specifying a size bigger than what a BLOB column in MySQL can hold, OpenJPA still creates only a BLOB column.

I think OpenJPA should be able to create the proper column type depending on the @Column annotation if present, or otherwise default at least to a MEDIUMBLOB to preserve cross-database compatibility as expected.

The simplest patch i can think of is setting blobTypeName="MEDIUMBLOB" in the MySQLDictionary constructor.

Otherwise, overriding the getTypeName to properly parse the length and return the correct BLOB/TEXT type for mysql.

Issue Links

• is related to: OPENJPA-1667 Incorrect column type for LOB streaming in MySQL
• relates to: OPENJPA-1870 Blob types override column definition from @Column annotation with MySQL