GORM - Update object without retrieving it first

Question

I'd like to be able to update a previously persisted object for which I have an id without having to retrieve it first. The main thing that I'm trying to avoid is having to copy multiple values into the object's fields when that object has been retrieved from the database. I have these values in a map with keys corresponding to the field names so it's trivial to create the object via a constructor with the map as an argument. Unfortunately, an object created this way results in a new database record when saved even though the id field is set to that of an existing record.

I'm currently using a slight variation on one of the examples shown here for copying Groovy class properties but it's not a very elegant solution for multiple reasons.

Basically I'd like to be able to do something like this:

class Foo {
    int a
    String b
}

def data = [id: 99, a: 11, b: "bar"]    //99 is the id of an existing record
def foo = new Foo(data)
foo.update()    //or some other comparable persistence mechanism

Thanks

Note that I was hoping to find something similar to the fictional update() statement above that doesn't require specifying the individual fields either via having to copy them into an object or in a SQL statement etc. — WXB13, Nov 13 '12 at 20:14

score 3 · Answer 1 · answered Nov 13 '12 at 08:13

3

You can use the executeUpdate method on the GORM domain class:

Foo.executeUpdate("update Foo f set f.a=:a, f.b=:b where f.id=:id", data)

answered Nov 13 '12 at 08:13

Andre Steingress

4,381
28
28

Yeah, I knew that. I was looking for something that allowed for an update without referencing the individual fields--basically something much less verbose. Thanks anyway. – WXB13 Nov 13 '12 at 17:45

Bob McCracken · Accepted Answer · 2012-11-17T20:48:11.760

3

As long as your map keys have the same name as your object properties, you can use executeUpdate without specifying the individual property names with a closure or function like the following:

def updateString = { obj, map ->
        def str = ""
        map.each { key, value ->
            str += "${obj}.${key}=:${key},"
        }

        return str[0..-2]
    }

    def data= [foo:"bar", machoMan:"RandySavage"]

In this case, println updateString("f", data) returns "f.foo=:foo,f.machoMan=:machoMan".

Then you can do this:

Foo.executeUpdate("update Foo f set ${updateString("f", data)}", data)

Or of course you could combine that all together into one closure or function.

edited Nov 17 '12 at 20:48

answered Nov 14 '12 at 18:41

Bob McCracken

376
1
4

This is an interesting approach. I'll have to play around with it to figure out how to set up a generic closure/function that can be passed just the object and the map (e.g. update(foo, data) ). – WXB13 Nov 17 '12 at 05:55
Oh yeah I suppose that would be useful. `foo.class.name` will get you the class name, and then hopefully the DB table name as well. – Bob McCracken Nov 17 '12 at 20:52

GORM - Update object without retrieving it first

2 Answers2