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From abdullah alamoudi <bamou...@gmail.com>
Subject Re: Metadata names generation
Date Wed, 24 Jun 2015 18:56:53 GMT
If that's the case, then I think we need to disallow using the "." since it
is used to access nested fields and can definitely cause ambiguity.

a clear case is where there is a data type with a field named "a.b" and
another field named "a" which has a nested field named "b".

Thoughts?


On Wed, Jun 24, 2015 at 9:51 PM, Steven Jacobs <sjaco002@ucr.edu> wrote:

> I think there is no completely user-friendly way around this. Basically our
> names allow ALL characters if they are incapsulated in quotes, so there
> isn't a character we can use that doesn't have the potential for ambiguity
> from the user's perspective. This is why I had to change the nested stuff
> in indexing to be a list of strings rather than a single string.
> Steven
>
> On Wed, Jun 24, 2015 at 11:43 AM, Chen Li <chenli@gmail.com> wrote:
>
> > In this case, there could be ambiguity in the names.  Does it matter?
> >
> > Chen
> >
> > On Wed, Jun 24, 2015 at 11:17 AM, Steven Jacobs <sjaco002@ucr.edu>
> wrote:
> >
> > > Fieldnames do allow these characters (both of them).
> > > Steven
> > >
> > > On Wed, Jun 24, 2015 at 11:15 AM, Chen Li <chenli@gmail.com> wrote:
> > >
> > > > I also prefer "." than "_".  Also want to confirm that field names
> > don't
> > > > allow these two characters.
> > > >
> > > > Chen
> > > >
> > > > On Wed, Jun 24, 2015 at 10:52 AM, Steven Jacobs <sjaco002@ucr.edu>
> > > wrote:
> > > >
> > > > > I second Young-Seek (especially since this is the syntax that users
> > > will
> > > > > use themselves for nested information in queries).
> > > > >
> > > > > Steven
> > > > >
> > > > > On Wed, Jun 24, 2015 at 10:40 AM, Young-Seok Kim <
> kisskys@gmail.com>
> > > > > wrote:
> > > > >
> > > > > > It seems better to use "." instead of "_" since "." is more
> > intuitive
> > > > (at
> > > > > > least to me) than "_".
> > > > > > For example, the FacebookUserType_address will be
> > > > > FacebookUserType.address.
> > > > > >
> > > > > > Best,
> > > > > > Young-Seok
> > > > > >
> > > > > > On Wed, Jun 24, 2015 at 6:31 AM, Mike Carey <dtabass@gmail.com>
> > > wrote:
> > > > > >
> > > > > > > Much cleaner!  Others should weigh in here to help finalize
the
> > > > > > > conventions....  Thoughts?
> > > > > > > On Jun 23, 2015 5:31 PM, "Ildar Absalyamov" <
> iabsa001@cs.ucr.edu
> > >
> > > > > wrote:
> > > > > > >
> > > > > > > > So the general solution is that the generated names
should
> > become
> > > > > less
> > > > > > > > verbose (consider previous examples):
> > > > > > > > 1) Anonymous fields naming scheme will change to
> outerTypeName
> > +
> > > > “_”
> > > > > +
> > > > > > > > fieldName, i.e. “Field_address_in_FacebookUserType”
is
> changed
> > to
> > > > > > > > “FacebookUserType_address”
> > > > > > > > 2) Anonymous collection item naming scheme stays the
same,
> i.e.
> > > > > > > > “Field_employment_in_FacebookUserType_ItemType”
is changed to
> > > > > > > > “FacebookUserType_employment_ItemType” (name is
changed
> because
> > > the
> > > > > > > > anonymous field employment naming was changed as described
> > > earlier)
> > > > > > > > 3) Union type completely seizes to exist in metadata
(it
> stays
> > in
> > > > the
> > > > > > > > object model though), i.e.
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> “Type_#1_UnionType_Field_end-date_in_Field_employment_in_FacebookUserType_ItemType”
> > > > > > > > is changed to
> “FacebookUserType_employment_ItemType_end-date”,
> > > > where
> > > > > > the
> > > > > > > > type metadata will have an additional field “Optional”
with
> > value
> > > > > > “true”.
> > > > > > > >
> > > > > > > > > On Jun 19, 2015, at 18:11, Ildar Absalyamov <
> > > iabsa001@cs.ucr.edu
> > > > >
> > > > > > > wrote:
> > > > > > > > >
> > > > > > > > > So I have done half of the fix, which is moved
name
> > generation
> > > > > logic
> > > > > > > out
> > > > > > > > of the Metadata node to the client.
> > > > > > > > > Up to that point nothing in Metadata format was
changed,
> > which
> > > > > makes
> > > > > > me
> > > > > > > > wonder whether I should proceed with the following
changes.
> > > > > > > > >
> > > > > > > > > As it could be seen from the previous email getting
rid of
> > > > > > > > union-inferred name generation would make auto generated
type
> > > names
> > > > > > less
> > > > > > > > scary, but not entirely.
> > > > > > > > > Having in mind what Mike mentioned earlier today,
should we
> > do
> > > > > > > something
> > > > > > > > about other auto generated type name cases?
> > > > > > > > >
> > > > > > > > >> On Jun 19, 2015, at 13:01, Ildar Absalyamov
<
> > > > iabsa001@cs.ucr.edu
> > > > > > > > <mailto:iabsa001@cs.ucr.edu>> wrote:
> > > > > > > > >>
> > > > > > > > >> Currently we are generating the names for
inner\anonymous
> > > types
> > > > in
> > > > > > the
> > > > > > > > following cases:
> > > > > > > > >> 1) Anonymous field in the record.
> > > > > > > > >> AQL Example:
> > > > > > > > >> create type FacebookUserType as closed {
> > > > > > > > >>         id: int32,
> > > > > > > > >>         name: string,
> > > > > > > > >>         address: {
> > > > > > > > >>              address_line: string,
> > > > > > > > >>              city: string
> > > > > > > > >>              state: string
> > > > > > > > >>      }
> > > > > > > > >>     }
> > > > > > > > >> The pattern for generating an anonymous field
name is
> > > "Field_" +
> > > > > > > > fieldName + "_in_" + outerTypeName, which translates
to
> > > > > > > > "Field_address_in_FacebookUserType" in the given example
> > > > > > > > >>
> > > > > > > > >> 2) Anonymous collection (ordered\unordered
list) item
> > > > > > > > >> create type FacebookUserType as closed {
> > > > > > > > >>         id: int32,
> > > > > > > > >>         name: string,
> > > > > > > > >>         employment: [{
> > > > > > > > >>              organization-name: string,
> > > > > > > > >>              start-date: date
> > > > > > > > >>              end-date: date?
> > > > > > > > >>      }]
> > > > > > > > >>     }
> > > > > > > > >> The pattern for generating an anonymous collection
item
> name
> > > is
> > > > > > > > collectionFieldName+_ItemType", which translates to
> > > > > > > > "Field_employment_in_FacebookUserType_ItemType" in
the given
> > > > example
> > > > > > > > >>
> > > > > > > > >> 3) Nullable fields
> > > > > > > > >> Same example as above could be used (end-date
field): the
> > > > pattern
> > > > > > for
> > > > > > > > generating a nullable field name is "Type_#" +
> > > > > fieldsNumberInUnoinList
> > > > > > +
> > > > > > > > "_UnionType_" + outerTypeName, which translates to
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> “Type_#1_UnionType_Field_end-date_in_Field_employment_in_FacebookUserType_ItemType"
> > > > > > > > in the given example.
> > > > > > > > >>
> > > > > > > > >> So you can see these auto generated names
could stack up
> > > pretty
> > > > > fast
> > > > > > > > and be completely incomprehensible. Just to give you
a small
> > > flavor
> > > > > of
> > > > > > > > that, here is one of the metadata datasets type definitions:
> > > > > > > > >>
> > > > > > > > >> open {
> > > > > > > > >>   DataverseName: STRING,
> > > > > > > > >>   DatatypeName: STRING,
> > > > > > > > >>   Derived: UNION(NULL, open {
> > > > > > > > >>       Tag: STRING,
> > > > > > > > >>       IsAnonymous: BOOLEAN,
> > > > > > > > >>       EnumValues: UNION(NULL, [ STRING ]),
> > > > > > > > >>       Record: UNION(NULL, open {
> > > > > > > > >>           IsOpen: BOOLEAN,
> > > > > > > > >>           Fields: [ open {
> > > > > > > > >>               FieldName: STRING,
> > > > > > > > >>               FieldType: STRING
> > > > > > > > >>             }
> > > > > > > > >>           ]
> > > > > > > > >>         }
> > > > > > > > >>       ),
> > > > > > > > >>       Union: UNION(NULL, [ STRING ]),
> > > > > > > > >>       UnorderedList: UNION(NULL, STRING),
> > > > > > > > >>       OrderedList: UNION(NULL, STRING)
> > > > > > > > >>     }
> > > > > > > > >>   ),
> > > > > > > > >>   Timestamp: STRING
> > > > > > > > >> }
> > > > > > > > >>
> > > > > > > > >> And here are couple of fields names, generated
for it :)
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> Type_#1_UnionType_Field_Record_in_Type_#1_UnionType_Field_Derived_in_DatatypeRecordType
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> Field_UnorderedList_in_Type_#1_UnionType_Field_Derived_in_DatatypeRecordType
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> Field_Fields_in_Type_#1_UnionType_Field_Record_in_Type_#1_UnionType_Field_Derived_in_DatatypeRecordType_ItemType
> > > > > > > > >>
> > > > > > > > >> Best regards,
> > > > > > > > >> Ildar
> > > > > > > > >>
> > > > > > > > >
> > > > > > > > > Best regards,
> > > > > > > > > Ildar
> > > > > > > > >
> > > > > > > >
> > > > > > > > Best regards,
> > > > > > > > Ildar
> > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
>



-- 
Amoudi, Abdullah.

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