diff --git a/ogr/ogrsf_frmts/pg/ogrpgdatasource.cpp b/ogr/ogrsf_frmts/pg/ogrpgdatasource.cpp
index 1c2c6a93b8e0..f38c9e7329e0 100644
--- a/ogr/ogrsf_frmts/pg/ogrpgdatasource.cpp
+++ b/ogr/ogrsf_frmts/pg/ogrpgdatasource.cpp
@@ -831,12 +831,12 @@ int OGRPGDataSource::Open(const char *pszNewName, int bUpdate, int bTestOpen,
             if (EQUAL(pszTypname, "geometry"))
             {
                 bHavePostGIS = TRUE;
-                nGeometryOID = atoi(pszOid);
+                nGeometryOID = static_cast<Oid>(strtoul(pszOid, nullptr, 10));
             }
             else if (CPLTestBool(CPLGetConfigOption("PG_USE_GEOGRAPHY", "YES")))
             {
                 bHaveGeography = TRUE;
-                nGeographyOID = atoi(pszOid);
+                nGeographyOID = static_cast<Oid>(strtoul(pszOid, nullptr, 10));
             }
         }
     }
diff --git a/ogr/ogrsf_frmts/pg/ogrpglayer.cpp b/ogr/ogrsf_frmts/pg/ogrpglayer.cpp
index a196317b7ce6..8e186860d7d5 100644
--- a/ogr/ogrsf_frmts/pg/ogrpglayer.cpp
+++ b/ogr/ogrsf_frmts/pg/ogrpglayer.cpp
@@ -564,7 +564,7 @@ OGRFeature *OGRPGLayer::RecordToFeature(PGresult *hResult,
     for (int iField = 0; iField < PQnfields(hResult); iField++)
     {
 #if defined(BINARY_CURSOR_ENABLED)
-        int nTypeOID = PQftype(hResult, iField);
+        const Oid nTypeOID = PQftype(hResult, iField);
 #endif
         const char *pszFieldName = PQfname(hResult, iField);