TAP-1.0 Erratum 5: VOTable usage in TAP 
Author: DAL WG
Date last changed: 2017-09-28
 Rationale 
The wording in 
TAP-1.0 in §~2.9 and §2.9.1 about the use of 
VOTable is somewhat inconsistent about the format of VOTable error documents. 
It is clear that §2.9 is discussing both successful and error outputs, and in the case of an error no 
TABLE element will normally be present, only one or more 
INFO elements. However, while the intention is clear from the fourth example in §2.9.1, it is not clear from the wording.
 Erratum Content 
The wording of §2.9 and §2.9.1 of TAP-1.0 is inconsistent with the rules for VOTable error documents. §2.9 says 
  - The VOTable must contain a RESOURCEelement identified with the attributetype='results', containing a singleTABLEelement with the results of the query.
and §2.9.1 says
  - The RESOURCEelement must contain, before theTABLEelement, ...
The inconsistency comes from the fact that in case of a response error no 
TABLE element will normally be present, only one or more 
INFO elements.
This Erratum removes the inconsistency by changing: 
-  first sentence in the third paragraph of Sec.~2.9 from
  - The VOTable must contain a RESOURCE element identified with the attribute type="results", containing a single TABLE element with the results of the query.
to
  - The VOTable must contain a RESOURCEelement identified with the attribute =type='results'=type='results'.  In case of successful job execution,
   this must contain exactly one TABLE element with the results of
   the query. [In case of job failure, the TABLE element may be absent.]
-  first paragraph of §2.9.1 from
  - The RESOURCEelement must contain, before theTABLEelement, anINFOelement with attributename="QUERY_STATUS". The value attribute must contain one of the following values:
to
  - The RESOURCEelement must contain anINFOelement with attributename="QUERY_STATUS"indicating the success of the operation. ForRESOURCEelements that contain aTABLEelement, thisINFOelement must appear lexically before theTABLE. The following values are defined for thisINFOelement'svalueattribute:
 Impact Assessment 
Since the wording changes introduced by this Erratum are only meant to better describe the usage of an existing recommendation (the VOTable one) inside the TAP-1.0 protocol, no effects on TAP-1.0 services and consuming application is foreseen.
 Note 
This Erratum was previously part of the TAP1Err1 Note still available on 
volute. The content presented here started from §6 of that Note at svn revision 2800.