Pg data source does not report error message in some cases

[Ari Jolma]

I have SQL

select "geom" as "geometryProperty","id" as "gml_id","pass" as "pass","usern" as "usern" from "test_auth" where ST_IsValid("geom") AND ((("user" = 'me') AND ("pass" = 'pass')) AND (geom && ST_MakeEnvelope(0,0,5,5)))

which, when given to ExecuteSQL lead to SoftStartTransaction... block of code in ogrpgdatasource.cpp. This SQL is flawed and leads to error but the SoftRollbackTransaction(); removes the error and it is not available any more below where the code tries to access it. The CPLError needs to be called before SoftRollbackTransaction();

[Even Rouault]

trunk r31319, branches/2.0 r31320 "PG: avoid reseting error potentially emitted by ExecuteSQL() (#6194)"

[Ari Jolma]

I would have expected that we keep the call to set the error message but call it before SoftRollbackTransaction.

However, the error text seems to be emitted. I'm confused. Why that happens?

[Even Rouault]

The error message is directly emitted by OGRPG_PQexec(). Previously there was no wrapper so each time code was necessary to emit a CPLError().