GQL Standard

October 4, 2023 – GQL Status Update

The Draft International Standard (DIS) ballot for 39075 Database Language  — GQL started on May 23, 2023 and ended on August 15,  2023. The result of the ballot was that twelve national bodies approved the GQL DIS ballot, zero national bodies disapproved, and eight national bodies abstained. 

Three national bodies and the ISO central secretariat included comments, for a total of 493 comments. The comments range from fairly minor editorial comments to significantly more complex issues. 

Since the DIS ballot closed, we have been working to resolve the comments. 

The GQL editors were able to resolve 186 of these comments without additional input. 

The remaining comments required concrete proposals. SC32 WG3 held a meeting the week of September 25, 2023 where we reviewed and took action on about 50 papers proposing comment resolutions. The editors are now applying the approved changes and in the next week or two will publish a draft. Paper authors then need to review the draft to ensure that proposals were applied correctly. This requires particular careful review when multiple papers addressed the same part of the document.

This leaves us with 72 comments that have not yet been resolved:

The 18 comments with a proposed solution are about various aspects of graph types. During the September 25th meeting, we reviewed a paper resolving these comments. However the paper was late and large so we are going to take more time and will review it again in a web conference the week of October 30.

The 45 comments that have been assigned will have proposals available in the next week or two. These will also be reviewed during the October 30th web conference.

The 9 comments that are still open include issues such as: 

• There are too many terms in Clause 3.

• If, during the comment resolution process, differences are found, we must insure that GQL has the same semantics as SQL/PGQ:2023 on the subset of the graph pattern language and expression syntax that is shared by them.

• Any additional editorial corrections or improvements discovered during the comment resolution process should also be addressed.

These remaining open comments are useful for identifying areas that should be reviewed in conjunction with resolving other comments. However, there are are not absolute solutions to things such as "too many terms in Clause 3, Definitions." When we get everything else resolved, these comments will be marked as resolved.

The next steps towards a published GQL standard are:

• WG3 web conference October 30 - November 2. This will be four 3-hour sessions where I expect to have ten or so proposals that resolve remaining comments.

• The editors will apply the papers and produce a draft for review by about November 15. 

• WG3 participants will review the application of  papers and look for any other lingering issues.

• If necessary, WG3 will have another web conference the week of November 27, 2023

• The GQL draft will be submitted to the ISO Central Secretariat (ISO CS) by December 8, 2023 for a Final Draft International Standard (FDIS) ballot.

• The FDIS ballot is 8 weeks and can be started fairly quickly. The FDIS should be completed by the end of January 2024.

• The FDIS will likely produce some editorial corrections after which GQL will be submitted to ISO CS for publication.

The publication process takes six to eight weeks so ISO/IEC 39075 Information technology — Database languages — GQL should be published in late March or early April of 2024!

May 16, 2023 – GQL Status Update

In February, 2023, the GQL standards committee  (ISO/IEC JTC1 SC32 WG3) had a week-long meeting in Zeist, Netherlands, where we reviewed and accepted papers that completed the resolution of all of the GQL CD2 comments. The editors applied the papers, the authors reviewed the application of papers, and in March, we held a web conference to review some last minute corrections. Following the March web conference, the editors did additional work and submitted the GQL draft to ISO to initiate a Draft International Standard (DIS) ballot. 

The DIS ballot has two phases, an 8-week period for the ISO editor to review the document, and a 12-week ballot. The GQL DIS ballot officially starts on 2023-05-23 and ends on 2023-08-15. The DIS ballot will produce some number of comments, most of which  (but probably not all) will be editorial. 

WG3 has a meeting scheduled for the last week of September, 2023. I expect that we will be able to resolve all of the DIS comments at the September meeting. If we only make editorial changes to the GQL draft, the standard could be published by the end of 2023. If we make technical changes to the GQL draft, we will have to hold an 8-week DIS2 ballot, in which case the GQL standard will be published in early 2024. The official designation will be:

ISO/IEC 39075 Information technology — Database languages — GQL

Even if we do make technical changes as the result of DIS ballot comments, those changes are likely to be fairly small corrections, not major syntax perturbations. At this point, the GQL specification is technically very stable.

Parts of the GQL specification, in particular the Graph Pattern Matching (GPM) language, have been technically stable since mid 2022. We have worked hard to keep GPM in GQL as identical as possible to GPM in SQL/PGQ - Property Graph Queries in SQL. SQL/PGQ contains two major capabilities:

• Syntax for creating a property graph view on top of existing SQL tables

• Syntax for including a property graph query (GPM) in a GRAPH_TABLE function in an SQL FROM clause.

The draft GQL standard builds on the Graph Pattern Matching language  and is a full DB language, including:

• DML – Create, Read, Update, Delete

• DDL – Create Graph Type, Create Graph, Create Graph from Graph Type

• Support for schema-fixed and schema-flexible variants

We held a DIS ballot on the next edition of the SQL standard (all eleven parts) last fall and completed the resolution of the SQL DIS comments during the February meeting. (It was a really busy meeting.) The SQL standard has been submitted to ISO for publication and we've had a couple of rounds of editorial corrections. I expect the next edition of the SQL standard to be officially published in the next couple of weeks, hopefully by the end of May, 2023. 

So, in short, we have a couple of more hurdles to complete the GQL standard, but those hurdles are in sight.

December 2, 2022 – GQL Status Update

At the end August, 2022, the GQL standards committee (ISO/IEC JTC1 SC32 WG3) initiated a second Committee Draft (CD2) consultation on the GQL draft. (This used to be a CD ballot, but as of July 2022 ISO changed the terminology for a CD from "ballot" to "consultation".) In any case, the CD2 period ended on 2022-10-26, with a fair number of comments. The breakdown of the CD2 comments is:

So far, about 25% of the comments have been resolved, either editorially, or through papers reviewed and excepted at the November WG3 meeting. WG3 participants have signed up to resolve another 29% of the comments.

Of the 239 comments for which participants have signed up, we have 14 papers addressing about 160 comments submitted for next week's WG3 web conference. In the following chart, slices identified by WG3:W24-nnn are  papers that have already been submitted. Slices with names instead of numbers are papers that are in process and not yet ready for review.

One of the challenges of using web conferences for meetings of an international committee is that there is no single good time. The WG3 meeting next week is three 3-hour sessions on Monday, Wednesday, and Thursday. Each session starts at 07:00 in Tokyo and Seoul, 06:00 in Beijing, 23:00 in Berlin, 22:00 in London, 17:00 in New York, and 14:00 in San Francisco.

We still have a lot of work to do, but we are on target to have the GQL draft ready to submit for a Draft International Standard (DIS) ballot in spring, 2023.

There are a lot of capabilities specified in the GQL draft. However, It does not have everything that every one will want. The Linked Data Benchmark Council (https://ldbcouncil.org/) has initiated a new activity, the LDBC Extended GQL Schema Working Group. The new working group is currently forming five sub-groups to focus on the areas:

• Use Cases and Requirements

• SHACL analysis

• DDL representation + Parser

• Visual representation

• Graph representation

This work will provide input to SC32 WG3 for the next version of the GQL standard and will probably produce an academic paper or two on theoretical underpinnings of property graph schemas.

July, 2022 – GQL Status Update

In June, SC32 WG3 had a two week meeting in Berlin, Germany. We had 10 to 12 people in the room and several more people included by web conference. We accomplished two major things.

1. We completed the work needed to initiate a Draft International Standard (DIS) ballot on eleven parts of ISO/IEC 9075 Information Technology — Database Language — SQL, including 9075-16 SQL/PGQ –Property Graph Queries in SQL. The documents will be sent to ISO Central Secretariat at the beginning of August. The DIS process is 20 weeks (8 weeks of preliminary ISO CS time then 12 weeks for the actual ballot), so the ballot should be complete by the end of December 2022.

2. We made significant progress on resolving the CD ballot comments on ISO/IEC 39075 Information Technology — Database Languages — GQL We are  going to conduct an 8-week second CD consultation (formerly called a ballot) starting in September. This will give us a chance to review the changes we've been making in response to first set of CD comments. We plan to initiate the GQL DIS in spring, 2023.

SQL/PGQ is interesting to people focused on GQL because the Graph Pattern Matching (GPM) language in SQL/PGQ is essentially identical to GPM in GQL. Since the technical work on SQL/PGQ is now stable, GPM in GQL is now stable.  For more information on GPM, take a look at the 2022 ACM SIGMOD paper Graph Pattern Matching in GQL and SQL/PGQ.

At the start of the Berlin WG3 meeting, we had resolved 311 comments. By the end of the Berlin meeting, we had resolved 532 comments, just under two-thirds of the total comments. The pie-chart now shows two classes of resolved comments, "1-resolved editorially" and "2-resolved". We still have a lot of work to do, but we accomplished a lot during the June meeting.

Papers resolving the comments that are assigned will be processed during the August WG3 web conference.

June, 2022 – GQL Status Update

It turns out that writing a database language standards is a lot of work, but we are making progress.

'We" are the participants in the international standards committee ISO/IEC JTC/1 SC/32 WG/3 Database Languages and the participants in the various national standards groups that send papers and experts to SC32 WG3.

The GQL standards project is officially ISO/IEC 39075 Information Technology — Database Languages — GQL 

SC32 WG3 initiated a Committee Draft (CD) ballot in November 2021. The ballot closed in February 2022 with over 800 comments. The breakdown of the comments is:

The GQL editors will resolve most Major (50) and Minor (196) Editorial comments – 31% of the comments. Many (most?) of the Language Opportunities (93) will be deferred to a future GQL version – 11%. That still leaves a lot of comments to resolve.

Since February, we have been made progress on comment resolution. As of the beginning of June, 2022, 311 comments have been resolved and WG3 participants have signed up to resolve another 125 comments.

The June 2022 WG3 meeting will process papers resolving the assigned comments as well as not yet assigned comments.

September, 2019 – GQL inaugurated as an official ISO project. See New Query Language for Graph Databases to Become International Standard for more information.

GQL is an upcoming International Standard language for property graph querying that is currently being created. The idea of a standalone graph query language to complement SQL was raised by ISO SC32/ WG3 members in early 2017, and is echoed in the GQL manifesto of May 2018. 

GQL supporters aim to develop a rock-solid next-generation declarative graph query language that builds on the foundations of SQL and integrates proven ideas from the existing openCypher, PGQL, GSQL, and G-CORE languages. The proposed SQL:202x Property Graph Query Extensions already build on these existing languages. 

GQL will incorporate this prior work, as part of an expanded set of features including regular path queries, graph compositional queries (enabling views) and schema support.

Site Purpose and Goals

This site serves as a hub for sharing information and ideas about the ongoing development of the GQL standard proposal. 

• Graph Query Language Requirements

• Use cases for specific capabilities

• Graph Query Language resources, conferences and workshops

• Updates on the progress of a formal GQL Standard.

To get more information or to get involved, please refer to the links on the Collaboration page.