Grails/GORM belongsTo Back Reference Naming - grails

Question

I created the domains in Grails to focus on the business logic behind our process. In several cases, this translates to a back reference that GORM generates that exceeds the Oracle limits and generates a "ORA-00972: identifier is too long" error. I was able to use the static mapping block to remap the long table name, but I can't figure out how to do the same for the generated back reference.
Without exposing any company confidential information, the following example illustrates the problem.
class UnfortunatelyLongClassName {
static mapping = {
table "long_class" // This works great!
}
List<Part> parts
static hasMany = [parts:Part]
}
class Part {
String name
// This generates UNFORTUNATELY_LONG_CLASS_NAME_ID and causes the error
static belongsTo = [UnfortunatelyLongClassName]
}
Rough DDL of the tables generated...
LONG_CLASS (
ID number(19, 0) not null,
VERSION number(19, 0) not null,
primary key (id),
);
PART (
ID number(19, 0) not null,
VERSION number(19, 0) not null,
NAME varchar2(255),
PARTS_IDX number(10, 0),
UNFORTUNATELY_LONG_CLASS_NAME_ID number(19, 0) not null,
primary key (id),
foreign key FK589895C372DB95A (UNFORTUNATELY_LONG_CLASS_NAME_ID) references UNFORTUNATELY_LONG_CLASS_NAME(ID)
);
Are there any static mapping commands or other Grails/GORM tricks to get this to create a shorter identifier?
If I use the following...
static belongsTo = [unfortunatelyLongClassName:UnfortunatelyLongClassName]
static mapping = {
unfortunatelyLongClassName column:"ulcn_id"
}
I get the following errors...
| Error 2012-07-24 17:53:49,060 [pool-7-thread-1] ERROR context.ContextLoader - Context initialization failed
Message: Error creating bean with name 'pluginManager' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.InvalidPropertyException: No property found for name [unfortunatelyLongClassName] for class [class mycompany.myproject.mypackage.Part]
Line | Method
->> 303 | innerRun in java.util.concurrent.FutureTask$Sync
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
| 138 | run in java.util.concurrent.FutureTask
| 886 | runTask in java.util.concurrent.ThreadPoolExecutor$Worker
| 908 | run in ''
^ 662 | run . . in java.lang.Thread
Caused by InvalidPropertyException: No property found for name [unfortunatelyLongClassName] for class [class mycompany.myproject.mypackage.Part]
->> 303 | innerRun in java.util.concurrent.FutureTask$Sync
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
| 138 | run in java.util.concurrent.FutureTask
| 886 | runTask in java.util.concurrent.ThreadPoolExecutor$Worker
| 908 | run in ''
^ 662 | run . . in java.lang.Thread
| Error 2012-07-24 17:53:49,094 [pool-7-thread-1] ERROR context.GrailsContextLoader - Error executing bootstraps: Error creating bean with name 'pluginManager' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.InvalidPropertyException: No property found for name [unfortunatelyLongClassName] for class [class mycompany.myproject.mypackage.Part]
Message: Error creating bean with name 'pluginManager' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.InvalidPropertyException: No property found for name [unfortunatelyLongClassName] for class [class mycompany.myproject.mypackage.Part]
Line | Method
->> 303 | innerRun in java.util.concurrent.FutureTask$Sync
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
| 138 | run in java.util.concurrent.FutureTask
| 886 | runTask in java.util.concurrent.ThreadPoolExecutor$Worker
| 908 | run in ''
^ 662 | run . . in java.lang.Thread
Caused by InvalidPropertyException: No property found for name [unfortunatelyLongClassName] for class [class mycompany.myproject.mypackage.Part]
->> 303 | innerRun in java.util.concurrent.FutureTask$Sync
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
| 138 | run in java.util.concurrent.FutureTask
| 886 | runTask in java.util.concurrent.ThreadPoolExecutor$Worker
| 908 | run in ''
^ 662 | run . . in java.lang.Thread

Answer 1

Use the Map syntax in belongsTo to generate the backlink and rename it via a mapping:
static belongsTo = [unfortunatelyLongClassName:UnfortunatelyLongClassName]
static mapping = {
unfortunatelyLongClassName column:"ulcn_id"
}
belongsTo should also work with fields in your Domain class, so you could do:
UnfortunatelyLongClassName unfortunatelyLongClassName
static belongsTo = UnfortunatelyLongClassName
static mapping = {
unfortunatelyLongClassName column:"ulcn_id"
}
Since the previous versions throw missing property exceptions, you could try creating the property with a short name and skipping the mapping block:
UnfortunatelyLongClassName ulcn
static belongsTo = UnfortunatelyLongClassName

Answer 2

What if you try to rename the id of the long class? Like:
static mapping = {
id name: 'simple_id_name'
}