Hi Maria,
Yes, actually it is.
The JOIN operation as it is defined in the ADQL schema allows for JOINs between more than 2 tables, recursive JOINs and all the types of JOINs that you listed below. I'm not sure if this is the kind of operation defined in ANSI SQL, but I'm pretty sure that not all RDBS accept that (at least Sybase doesn't). That's why I prefered to leave it apart just like the XMatch.
Cheers,
Aurelien
> Hi Aurelien,
>
> Just reviewed your xslt to convert ADQL/x into SQL (nice job!) and I
> realized there is no elements to define JOIN clauses.
>
>
> http://www.ivoa.net/xml/ADQL/v1.0 includes JOINS.
>
> + <xs:simpleType name="jointTableQualifierType">
> - <xs:annotation>
> <xs:documentation>Denotes the type of a Join
> operation</xs:documentation>
> </xs:annotation>
> - <xs:restriction base="xs:string">
> <xs:enumeration value="LEFT_OUTER" />
> <xs:enumeration value="RIGHT_OUTER" />
> <xs:enumeration value="FULL_OUTER" />
> <xs:enumeration value="INNER" />
> <xs:enumeration value="CROSS" />
> </xs:restriction>
> </xs:simpleType>
> + <xs:complexType name="joinTableType" mixed="false">
>
>
> Is the lack of JOIN element intended?
>
> Thanks
>
> Maria
Received on 2005-09-21Z19:04:30