RE: [odata] Agenda for OData TC meeting on 2017-06-01

[16:02] Hubert Heijkers (IBM): Good morning Mike, it appears it is just the two of us ;-?

[16:02] anonymous morphed into George Ericson (Dell)

[16:02] Ralf Handl (SAP SE): Me too

[16:03] Ralf Handl (SAP SE): Sorry for being late

[16:03] Hubert Heijkers (IBM): :D No worries

[16:04] Ralf Handl (SAP SE): Weekly meeting of the OData TC.

Dial-in information: https://www.oasis-open.org/apps/org/workgroup/odata/download.php/56760/latest

Online chat room: http://webconf.soaphub.org/conf/room/odatatc

Screen sharing: https://sap.emea.pgiconnect.com/OData-TC/

[16:08] Ralf Handl (SAP SE): Voting Members: 5 of 11 (45%) (used for quorum calculation)

[16:09] Ralf Handl (SAP SE): Agenda

1.Roll call [8:00 am PT]

a.Self-registration link: https://www.oasis-open.org/apps/org/workgroup/odata/event.php?event_id=43980

[16:10] Ralf Handl (SAP SE): Voting Members: 6 of 11 (54%) (used for quorum calculation)

[16:10] Ralf Handl (SAP SE): Thanks to Matt!

[16:10] Ralf Handl (SAP SE): 2.Approve agenda [8:05 am PT]

[16:11] Ralf Handl (SAP SE): Agenda is approved

[16:11] Ralf Handl (SAP SE): 3.Approve minutes from previous meeting(s) [8:10 am PT]

a.Minutes from May 18, 2017 TC meeting: https://www.oasis-open.org/committees/download.php/60763/odata-meeting-175_on-20170518-minutes.html

[16:11] Ralf Handl (SAP SE): Minutes are approved

[16:11] Ralf Handl (SAP SE): 4.Review action items [Action item list: https://www.oasis-open.org/apps/org/workgroup/odata/members/action_items.php] [8:15am PT]

a.Action items due

i.None

[16:11] Ralf Handl (SAP SE): 5.V4.01 [8:20 am PT]

a.Document walkthrough

[16:12] Ralf Handl (SAP SE): coming soon...

[16:12] Ralf Handl (SAP SE): Switching to issues

[16:12] Ralf Handl (SAP SE): ii.ODATA-1075 Introduce subsetof operator for checking whether a collection is a subset or equal to another collection

[16:13] Michael Pizzo: In reviewing the application, three questions came up:

1) is [1,1,2] subsetof [1,2] ? (do elements of the left operand have to occur at least as many times in the right operand)

For ordered collections:

2) is [3,1] subsetof [4,1,3]? (does order matter)

3) is [4,3] subsetof [4,1,3]? (can sequence have gaps)

For unordered collections both #2 and #3 should be true

[16:16] Ralf Handl (SAP SE): Hubert and Mike: tendency for items in right operand having to occur at least as many times as in left operand, so 1) would be false

[16:20] Ralf Handl (SAP SE): Hubert: tendency for ordering should not matter, introduce a separate operator for "subsequence preserving order"

[16:20] Michael Pizzo: Also need to define behavior if one is unordered and one is not ordered.

[16:21] Michael Pizzo: Option: subsetof is always unordered. a "contains" operator could apply only to ordered collections to take into account ordering.

[16:22] Michael Pizzo: What about null values?

[16:23] Michael Pizzo: null value is a value like any other value; you have to have at least as many null values in the right operand as the left

[16:28] Michael Pizzo: Proposal: define subsetof always to require that each element of the left operand occur at least as many times in the right operand, and that order does not matter. If we have someone asking for an operator that requires preservation of order with ordered collections we can add one at that time.

[16:33] Michael Pizzo: General question: when do we use functions and when do we use operators?

[16:33] Michael Pizzo: Functions are extensible. Operators have to be defined by TC.

[16:34] Michael Pizzo: Ralf: should we rename to "subCollectionOf" so it doesn't imply operands are sets.

[16:35] Ralf Handl (SAP SE): https://en.wikipedia.org/wiki/Subsequence

[16:35] Michael Pizzo: subSequence could be used for the ordered comparison.

[16:36] Michael Pizzo: For subsequence (as defined in Wikipedia) [4,3] would be a subsequence of [4,1,3].

[16:39] Michael Pizzo: Wikipedia defines a subset operator for "multisets":

[16:39] Ralf Handl (SAP SE): https://en.wikipedia.org/wiki/Multiset - essentially what our unordered collections are

[16:39] Michael Pizzo: The set indicator function of a subset is smaller than or equal to that of the superset

A  B   x , 1 A ( x )  1 B ( x ) . {\displaystyle A\subseteq B\Leftrightarrow \forall x,\,\mathbf {1} _{A}(x)\leq \mathbf {1} _{B}(x).}

[16:45] Hubert Heijkers (IBM): [4,1,5] contains [1,5]

[16:45] Ralf Handl (SAP SE): [4,1,5] contains [4,5] eq false

[16:46] Hubert Heijkers (IBM): [4,5] sequenceof [4,1,5] eq true

[16:46] Hubert Heijkers (IBM): [4,5] subsequenceof [4,1,5] eq true

[16:46] Ralf Handl (SAP SE): contains([4,1,5],[1,5]) --> true

[16:47] Ralf Handl (SAP SE): contains('abc','ab')

[16:47] Ralf Handl (SAP SE): contains(Firstname,'al')

[16:48] Ralf Handl (SAP SE): $filter=contains(Firstname,'al')

[16:50] George Ericson (Dell): How is case covered?  'Al' vs 'al'

[16:50] Hubert Heijkers (IBM): Propose we, apart from contains, also overwrite the startswith, endswith, indexof and substring??? functions with versions that accept collections

[16:54] Ralf Handl (SAP SE): only for ordered collections

[16:54] Ralf Handl (SAP SE): Strings essentially are ordered collections of characters

[16:55] Ralf Handl (SAP SE): Need also subsequenceof and subsetof, either as functions or as operators

[16:55] Michael Pizzo: Summary:

From 2017-6-1 discussion:

1) elements of the left operand have to occur at least as many times in the right operand (sos [1,1,2] subsetof [1,2]  => false

2) subsetof should never take order (or gaps) into account:

   i [3,1] subsetof [4,1,3] => true

  ii [4,3] subsetof [4,1,3] => true

3) for ordered collections, a "subsequence" operator could take order into account. subsequence is defined by Wikipedia to ignore gaps:

   i [3,1] subsetof [4,1,3] => false

  ii [4,3] subsetof [4,1,3] => true

4) for ordered collections, an operator that takes gaps into account is really a "contains":

   i [3,1] contains [4,1,3] => false

  ii [4,3] contains [4,1,3] => false

5) for ordered collections we could also define startswith, endswith, and indexof.

Question: which should we add now (versus wait for scenarios for) and should we add as functions or as operators?

[16:58] Hubert Heijkers (IBM): ~/Products?$filter=contains(CustomersThatBoughtThisProduct,[MostFavoriteCustomer(),LeastFavoriteCustomer]) eq true

[17:01] Hubert Heijkers (IBM): ~/Products?$filter=contains(CustomersThatBoughtThisProduct,[{"@odata.id":"Customers('MostFavoriteCustomerID')"},{"@odata.id":"Customers('LeastFavoriteCustomerID')"}]) eq true

[17:11] Michael Pizzo: Updated Proposal

1) subsetOf always requires that each element of the left operand occur at least as many times in the right operand, and that order does not matter so:

    subsetof([1,1,2],[1,2])  => false

subsetof should never take order (or gaps) into account:

    subsetof([4,1,3],[3,1]) => true

    subsetof([4,1,3],[4,3]) => true

2) for ordered collections, add a "subsequenceof" function that takes order into account and ignores gaps:

    subsequenceof([4,1,3], [3,1])  => false

    subsequenceof([4,1,3],[4,3]) => true

3) add support for ordered collections to contains, startswith, endswith, indexof, and substring, that takes gaps into account.

[17:13] Hubert Heijkers (IBM): I move to resolve ODATA-1075 as per the amended proposal.

[17:15] Michael Pizzo: updated:

Restrict "in" to mean just "member of"

Add "subsetof" function:

1) subsetOf always requires that each element of the left operand occur at least as many times in the right operand, and that order does not matter so:

    subsetof([1,2],[1,1,2])  => false

subsetof should never take order (or gaps) into account:

    subsetof([4,1,3],[3,1]) => true

    subsetof([4,1,3],[4,3]) => true

2) for ordered collections, add a "subsequenceof" function that takes order into account and ignores gaps:

    subsequenceof([4,1,3], [3,1])  => false

    subsequenceof([4,1,3],[4,3]) => true

3) add support for ordered collections to contains (that takes gaps into account) as well as startswith, endswith, indexof, and substring.

[17:16] Ralf Handl (SAP SE): indexof('Alfred','lf') --> 1

[17:16] Ralf Handl (SAP SE): contains('Alfred','lf') --> true

[17:19] Ralf Handl (SAP SE): hassubset([0,1,2],[1,2]) --> trze

[17:19] Michael Pizzo: alternate (clearer) naming:

Restrict "in" to mean just "member of"

Add "hassubset" function:

1) hassubset always requires that each element of the right argument occurs at least as many times in the left argument, and that order does not matter so:

    hassubset([1,2],[1,1,2])  => false

hassubset should never take order (or gaps) into account:

    hassubset([4,1,3],[3,1]) => true

    hassubset([4,1,3],[4,3]) => true

2) for ordered collections, add a "hassubsequence" function that takes order into account and ignores gaps:

    hassubsequence([4,1,3], [3,1])  => false

    hassubsequence([4,1,3],[4,3]) => true

3) add support for ordered collections to contains (that takes gaps into account) as well as startswith, endswith, indexof, and substring.

[17:20] Hubert Heijkers (IBM): I move to resolve ODATA-1075 as per the latest amended proposal.

[17:20] Michael Pizzo: I second

[17:20] Ralf Handl (SAP SE): ODATA-1075 is resolved as proposed

[17:24] Ralf Handl (SAP SE): Break until 17:30 CEST

[17:33] Stefan Hagen: Review / Walk-Through of CSDL XML Representation  https://www.oasis-open.org/committees/download.php/60499/odata-csdl-xml-v4.01-wd02-2017-04-10.docx started.

[18:18] Ralf Handl (SAP SE): Sorry,have to dial in again

[18:52] Stefan Hagen: Ready with the CSDL XML

[18:52] Ralf Handl (SAP SE): 6.Next meeting [9:50 am PT]

a.Thursday June 08, 2017 during 8-11 am PDT (17:00-20:00 CEST)  one hour longer  already confirmed

b.Thursday June 14, 2017 during 8-10 am PDT (17:00-19:00 CEST)?

[18:53] Ralf Handl (SAP SE): b.Thursday June 15, 2017 during 8-10 am PDT (17:00-19:00 CEST)?

[18:54] Ralf Handl (SAP SE): Public holiday in Germany

[18:54] Ralf Handl (SAP SE): Hubert is out

[18:54] Ralf Handl (SAP SE): George can't attend

[18:54] Ralf Handl (SAP SE): Mike can't make June 22

[18:57] Ralf Handl (SAP SE): Mike: get documents out next week

[18:57] Ralf Handl (SAP SE): Make it a four-hour meeting?

[18:59] Ralf Handl (SAP SE): 8-12 am PDT 17:00-21:00 CEST

[19:00] Ralf Handl (SAP SE): a.Thursday June 08, 2017 during 8-12 am PDT (17:00-21:00 CEST)  two hours longer

[19:00] Ralf Handl (SAP SE): Meeting is adjourned

From: odata@lists.oasis-open.org [mailto:odata@lists.oasis-open.org] On Behalf Of Handl, Ralf
Sent: Mittwoch, 31. Mai 2017 11:29
To: odata@lists.oasis-open.org
Subject: [odata] Agenda for OData TC meeting on 2017-06-01

Here [1] is a draft agenda for the OData TC (Technical Committee) meeting scheduled on Thursday June 01, 2017 during 7-10 am PDT (16:00-19:00 CEST). For additional information, such as dial-in details and chat room, refer to [2]. For TC timeline, see [3]. Feel free to suggest additions or modifications.

Thanks.

[1] Agenda

1. Roll call [8:00 am PT]

a. Self-registration link: https://www.oasis-open.org/apps/org/workgroup/odata/event.php?event_id=43980

2. Approve agenda [8:05 am PT]

3. Approve minutes from previous meeting(s) [8:10 am PT]

a. Minutes from May 18, 2017 TC meeting: https://www.oasis-open.org/committees/download.php/60763/odata-meeting-175_on-20170518-minutes.html

4. Review action items [Action item list: https://www.oasis-open.org/apps/org/workgroup/odata/members/action_items.php] [8:15am PT]

a. Action items due

i. None

5. V4.01 [8:20 am PT]

a. Document walkthrough