func chunkdata(c *mgo.Collection) {
var err error
// Enable a compund key for the x, y and z coordinate.
index := mgo.Index{
Key: []string{"x", "y", "z"}, // Set a compound index
Unique: true,
DropDups: true,
}
err = c.EnsureIndex(index)
if err != nil {
log.Println("chunkdb EnsureIndex compound", err)
}
// Define another key for the avatar ID
err = c.EnsureIndexKey("avatarID")
if err != nil {
log.Println("chunkdb EnsureIndex avatarID", err)
}
}