JPA/Hibernate DDL generation; CHAR vs. VARCHAR

java database hibernate jpa hibernate-annotations
Jeff Walker picture Jeff Walker · Feb 18, 2010 · Viewed 13.9k times · Source

I have a JPA/Hibernate data model that I am using the Hibernate hbm2ddl tool to generate database DDL. I have some strings that should be CHAR and some that may be VARCHAR in the database. I want to minimize hand editing of the DDL (I realize that some will have to happen).

Anyone know how I should go about this? I realize that I can make all Strings VARCHARS or CHARS via a hacked dialect, but that isn't what is always appropriate in the database.

I would like to be able to do this with annotations or aop, avoiding custom column definition text in my classes.

Thanks.

Answer

Markus Knittig picture Markus Knittig · Feb 18, 2010

Annotate the strings you want to map to a CHAR in the database with @Column(columnDefinition="CHAR(<your-char-length>)").

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