Problems with SQLite
This issue applies for database views that use xbob.dbs with SQLite.
After several fetches in the database (during the execution of the next method in the view), the SQLAlchemy raises the exception "Cannot operate on a closed database".
For some reason the connection with the database closes in the middle of the execution.
A workaround was done redefining (inside the view) the pool configuration to NullPool(http://docs.sqlalchemy.org/en/latest/core/pooling.html#sqlalchemy.pool.NullPool).
This works, but we have no clue what is going on.
This bug keeps track of this issue.