Re: Proposal of hierachical queries (a la Oracle)

On Thu, 2002-11-14 at 06:52, Evgen Potemkin wrote:
> Hi there!
>
> I want to propose the patch for adding the hierarchical queries posibility.
> It allows to construct queries a la Oracle for ex:
> SELECT a,b FROM t CONNECT BY a PRIOR b START WITH cond;B

Great addition. But please use the SQL 99 syntax for recursive queries
(if you need the full segment, I can send them to you):

Section 7.13 of Part 2:

Format

<search or cycle clause> ::=
<search clause>
| <cycle clause>
| <search clause> <cycle clause>

<search clause> ::=
SEARCH <recursive search order> SET <sequence column>

<recursive search order> ::=
DEPTH FIRST BY <sort specification list>
| BREADTH FIRST BY <sort specification list>

<sequence column> ::= <column name>

<cycle clause> ::=
CYCLE <cycle column list>
SET <cycle mark column> TO <cycle mark value>
DEFAULT <non-cycle mark value>
USING <path column>

<cycle column list> ::=
<cycle column> [ { <comma> <cycle column> }... ]

<cycle column> ::= <column name>

<cycle mark column> ::= <column name>

<path column> ::= <column name>

<cycle mark value> ::= <value expression>

<non-cycle mark value> ::= <value expression>

--
Rod Taylor <rbt(at)rbt(dot)ca>