LEFT JOIN and ODBC

Hello all,

I use PostgreSQL through ODBC with MSACCESS. In access I 
have the following query with several LEFT JOIN clauses. 

SELECT idvshelykod.sorszam, idvshelykod.helykod, 
idvshelykod.eloirat1, idvshelykod.eloirat2, a.a_hatas, b.b_hatas, 
c.c_hatas, d.mg_ic50, d.mhs_ic50, d.mg_tox, d.mhs_tox
FROM (((idvshelykod LEFT JOIN c1qfizio ON idvshelykod.helykod 
= a.helykod) LEFT JOIN b ON idvshelykod.helykod = b.helykod) 
LEFT JOIN c ON idvshelykod.helykod = c.helykod) LEFT JOIN d 
ON idvshelykod.helykod = d.helykod;


Now, I want to produce the same result from PostgreSQL with 
PH3, but I know that PGSQL does not support LEFT JOIN. I also 
know that the ODBC driver PostgreSQLize the access query so I 
have carefully read the sql audit file:  

conn=46022972, query='SELECT "helykod" ,"b"."oid" FROM "b" 
ORDER BY "helykod"  '   [ fetched 10902 rows ]
conn=46008444, query='SELECT "helykod" ,"idvshelykod"."oid" 
FROM "idvshelykod" ORDER BY "helykod"  '   [ fetched 11068 rows ]
conn=46022972, query='SELECT "helykod" ,"d"."oid" FROM "d" 
ORDER BY "helykod"  '   [ fetched 1161 rows ]
conn=46022972, query='SELECT "helykod" ,"a"."oid" FROM "a" 
ORDER BY "helykod"  '   [ fetched 267 rows ]
conn=46022972, query='SELECT "helykod" ,"c"."oid" FROM "c" 
ORDER BY "helykod"  '   [ fetched 267 rows ]
conn=46008444, query='SELECT "helykod" ,"b_hatas"  FROM "b" 
ORDER BY "helykod"  '   [ fetched 10902 rows ]
conn=46022972, query='SELECT "sorszam" ,"eloirat1" ,"eloirat2" 
,"helykod"  FROM "idvshelykod" ORDER BY "helykod"  '   [ fetched 11068 rows ]
conn=46022972, query='SELECT "helykod" ,"c_hatas"  FROM "c" 
ORDER BY "helykod"  '   [ fetched 267 rows ]
conn=46022972, query='SELECT "helykod" ,"a_hatas"  FROM "a" 
ORDER BY "helykod"  '   [ fetched 267 rows ]
conn=46022972, query='SELECT "helykod" ,"mg_ic50" 
,"mhs_ic50" ,"mg_tox" ,"mhs_tox"  FROM "d" ORDER BY 
"helykod"  '   [ fetched 1161 rows ]

and from this series of query the ODBC produce the desirable 
output.

What is the algorithm for postgresqlize the access query? 
How can I see the exact query sent to the postmaster daemon 
from ODBC?
Or simply, how can I postgresqlize my query?

Laszlo Molnar

Gedeon Richter Ltd.
Hungary