mysql - Images at Lightswitch v3.0: "Invalid URI: The Uri string is too long." -

i got simple lightswitch - silverlight based - web client. client.csproj , server.csproj saying lightswitchversion v3.0. runs on

• visual studio 2012 update 4
• lightswitch extensibility toolkit vs11

• i have 2 extension, both selected:

  • lightswitch cosmopolitan shell , theme
  • microsoft lightswitch extensions

and got mysql table

create table `images` (   `id` int(11) not null auto_increment,   `legend` varchar(200) not null,   `preview` blob,   `createdat` timestamp not null default current_timestamp,   primary key (`id`) ) engine=innodb auto_increment=3 default charset=utf8; 

and declared preview field image type in data source before created screen table. running application greets me this

using lightswitch 2.0 runs fine. since i've upgraded v3.0 issue spoiling :-(

i've not run across myself interest piqued. :)

it seems odata layer using contents of blob column ensure data concurrency , that's uri long. in native sql server table, can add rowversion column , selected concurrency purposes - lightswitch intrinsic database automatically in fact. understanding mysql doesn't have equivalent rowversion type.

the workaround create column on mysql table incremented mysql trigger on every update, making de facto concurrency field. update datasource , edit .lsml file add <useforconcurrency /> attribute column.

full discussion on https://social.msdn.microsoft.com/forums/vstudio/en-us/44581489-438d-4844-8194-0b4a0a41e56f/exception-invalid-uri-the-uri-string-is-too-long?forum=lightswitch