ADQL 2.1 Proposed Recommendation: Request for Comments

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ADQL defines an SQL-like grammar adapted for astronomical purpose. It is especially used by the TAP (Table Access Protocol) standard.

Latest version of ADQL can be found at:

• https://www.ivoa.net/documents/ADQL/20230418/index.html

Reference Interoperable Implementations

• DACHS
• VOLLT/ADQLLib (branch adql2.1)

Implementations Validators

Two ADQL parsing validators available in the GitHub repository named Lyonetia:

• One based on DACHS: src/adql/gavo
• One based on VOLLT: src/adql-validator

Both validators work offline and with no assumption on a specific database schema.

A GitHub CI workflow is set up in this repository. It validates all test queries available in the src/adql/ivoa directory thanks to the ADQL validator based on VOLLT.

Two badges are visible on top of the README.md document. The first one (named "Validator test") indicates whether the ADQL validator based on VOLLT compiled successfully or not. The second one (named "ADQL Validation) indicates whether all test queries passed or not. An HTML report is visible by clicking on this second badge (after clicking on the badge, click on the "Master" page to see it). It shows which test file run and which tests failed.

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Comments from the IVOA Community during RFC/TCG review period: 25-Apr-2023 - 6-Jun-2023

The comments from the TCG members during the RFC/TCG review should be included in the next section.

In order to add a comment to the document, please edit this page and add your comment to the list below in the format used for the example (include your Wiki Name so that authors can contact you for further information). When the author(s) of the document have considered the comment, they will provide a response after the comment.

Additional discussion about any of the comments or responses can be conducted on the WG mailing list. However, please be sure to enter your initial comments here for full consideration in any future revisions of this document

• Sample comment by WikiName
  • Response (by WikiName)

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Comments from TCG member during the RFC/TCG Review Period: 25-Apr-2023 - 20-Jun-2023

WG chairs or vice chairs must read the Document, provide comments if any (including on topics not directly linked to the Group matters) or indicate that they have no comment.

IG chairs or vice chairs are also encouraged to do the same, althought their inputs are not compulsory.

TCG Chair & Vice Chair

Applications Working Group

Data Access Layer Working Group

Data Model Working Group

Grid & Web Services Working Group

Registry Working Group

Semantics Working Group

Data Curation & Preservation Interest Group

Interesting new features - thank Greg and all!

It looks good, more user-friendly, even if the migration needs important work for data-center (eg: WITH, CAST, geometrical functions, units)

Details :

• (4.2.7) "coord_value" is not defined.
• (4.2.13) is it possible to use boolean instead of values {0,1} for CONTAINS ?
• (4.3) can you add link to UDF functions validated by IVOA (ivo_..) ?
• (4.6.1) remove item "the columns in the operands SHOULD have the same metadata, e.g. units, UCD, etc." -
  Tests should be limited to datatype - "same UCD" is clearly wrong (eg.: JOIN on primary-foregin key use meta.id;id.main and meta.id) , furthermore VOTable have not always UCD.

Coord syst: Coordinate system parameter deprecation has impacts.
For instance, coordinate system used in VizieR tables depends of each catalogues.
The coord syst is important in case of crossmatch (from an other table or from an UPLOAD)

If the parameter is removed, it requires;

• TO FIND A WAY TO REPORT THE NATIVE COORDINATE SYSTEM TO USER - in TAP_SCHEMA for instance
• to use UDF functions to make the conversion (is it possible to add with explicit example using UDF)

Notre : (4.2.16) COORDSYS function looks strange if system is removed from geometrical function - it asks a background ADQL processing

Education Interest Group

Knowledge Discovery Interest Group

Operations Interest Group

Radio Astronomy Interest Group

Solar System Interest Group

Theory Interest Group

Time Domain Interest Group

Standards and Processes Committee

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TCG Vote : 6-Jun-2023 - 20-Jun-2023

If you have minor comments (typos) on the last version of the document please indicate it in the Comments column of the table and post them in the TCG comments section above with the date.

Group	Yes	No	Abstain	Comments
TCG
Apps
DAL
DM
GWS
Registry
Semantics
DCP
Edu
KDIG
Ops
Radio
SSIG
Theory
TD
<nop>StdProc

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