Actually, the explain plan was from a pattern in an earlier testcase that
also failed.  The one listed has this explain plan.
REPORT
VARCHAR  {  RDF_QUAD_POGS 8 rows(s_10_2_t0.S)  P = ##type , O =
#/APIConsumer G = #/    Precode:  0: S := Call __id2in (s_10_2_t0.S)   5:
BReturn 0 RDF_QUAD_GS unq 0.64 rows ()   inlined G = #/ , S =
s_10_2_t0.S RDF_QUAD_SP
10 rows(s_10_2_t1.P)   inlined S = k_s_10_2_t0.S RDF_QUAD_POGS 0.3
rows(s_10_2_t1.O)   inlined P = k_s_10_2_t1.P S = k_s_10_2_t0.S , G =
#/   After
code:   0: P := Call __id2in (s_10_2_t1.P)  5: O := Call __ro2sq
(s_10_2_t1.O)   10: BReturn 0  Select (S, P, O) } No. of rows in result: 20


On 20 February 2014 16:05, Quentin <quent...@clearbluewater.com.au> wrote:

> This appears to be an intermittent error that pops up every few weeks,
> restarting the DB usually resolves it though not this time.
>
> The query that fails is of the form:
>
> sparql
> prefix o: <http://myOntology/>
>
> select *
> from <http://myGraph/>
>  {
>
> ?S a o:myClass .
> #?S ?P ?O .
> }
> ====
> It works until I remove that comment, correctly returning three bindings
> for ?S.  Once that comment is removed, zero bindings are returned.  If I
> comment the class line and just return SPO, I can find the ?S in the
> triples that matches the class binding.
>
> The explain plan is this:
> REPORT
> VARCHAR  { RDF_QUAD_POGS 8 rows(s_11_2_t0.S)   P = ##type , O = #/MyClass
> G = #/   Precode:  0: S := Call __id2in (s_11_2_t0.S)   5: BReturn 0 
> RDF_QUAD_GS
> unq 0.5 rows ()   inlined G = #/ , S = s_11_2_t0.S RDF_QUAD_SP 8.3
> rows(s_11_2_t1.P)   inlined S = k_s_11_2_t0.S RDF_QUAD_POGS 0.28
> rows(s_11_2_t1.O)   inlined P = k_s_11_2_t1.P S = k_s_11_2_t0.S , G = #/   
> After
> code:   0: P := Call __id2in (s_11_2_t1.P)  5: O := Call __ro2sq
> (s_11_2_t1.O)   10: BReturn 0  Select (S, P, O) } No. of rows in result:
> 20
>
> Debug log under trace_on shows nothing unusual.
>
> The instance is:
> Version 7.0.1-dev.3207-pthreads as of Feb  3 2014
> Compiled for Linux (x86_64-unknown-linux-gnu)
>
> I've quarantined the running instance of the DB and it consistently fails
> as above.  This behaviour began just a few hours ago, queries of this sort
> performed perfectly this morning and then began failing abruptly with no
> obvious reason why.
>
> I'm not sure it's related but when I cloned the running instance and
> started the DB on the clone, the log includes this error:
> 05:01:06 ERROR: Error executing a server init statement : 22023: SR528:
> Uninitialized property qmfOkForAnySqlvalue in JSO instance <
> http://www.openlinksw.com/virtrdf-data-formats#default-iid> of type <
> http://www.openlinksw.com/schemas/virtrdf#QuadMapFormat> --
>  DB.DBA.RDF_QUAD_FT_UPGRADE ()
>
>
> --
> Quentin | Clear Blue Water Pty Ltd
> quent...@clearbluewater.com.au
>



-- 
Quentin | Clear Blue Water Pty Ltd
quent...@clearbluewater.com.au
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