[odb-users] Data migration in SQLite

[Alexander Igorevich]

> On Dec 13, 2016, at 5:34 PM, Boris Kolpackov <boris at codesynthesis.com> wrote:
> 
> Hi Alexander,
> 
> Alexander Igorevich <alejandro_pnz at icloud.com> writes:
> 
>> #pragma db model version(2, 2, open)
>> 
>> #pragma db model version(1, 1, closed)
> 
> This means no migration is possible from version 1 to 2 which means
> you should end up here:
> 
> 
>>  if (v < bv)
>>  {
>>    // Error: migration from this version is no longer supported.
>>  }
> 
> Did you actually run it under the debugger to examine the control
> flow?
> 
> Boris


Yea, I run it under debugger - it works like should works - after adding new class (2nd version),
running next code segment:

for (v = schema_catalog::next_version (db, v);
       v <= cv;
       v = schema_catalog::next_version (db, v))
  {
    transaction t (db.begin ());
    schema_catalog::migrate_schema_pre (db, v);

    // Data migration goes here.

    schema_catalog::migrate_schema_post (db, v);
    t.commit ();
  }
I’ve tried to use different functions at this place - schema_catalog::migrate_schema_pre, schema_catalog::migrate_schema_post, schema_catalog:migrate_schema, schema_catalog::migrate_data, but no one of them doesn’t add new class in the database. If I re-create database, this class is added perfectly. How can I add new class using migrate function of the ODB?