[dataimport, migration] more fixes in the spirit of a6c32edabc8d:
[entity, metadata] huuum, use resolvable url as cwuri... And fix existing ones.
Closes #3390388
from yams import schema2sql as y2sql
dbhelper = repo.system_source.dbhelper
rdefdef = schema['CWSource'].rdef('name')
attrtype = y2sql.type_from_constraints(dbhelper, rdefdef.object, rdefdef.constraints).split()[0]
cursor = session.cnxset['system']
sql('UPDATE entities SET asource = source WHERE asource is NULL')
dbhelper.change_col_type(cursor, 'entities', 'asource', attrtype, False)
dbhelper.change_col_type(cursor, 'entities', 'source', attrtype, False)
dbhelper.change_col_type(cursor, 'deleted_entities', 'source', attrtype, False)