Fetch first rows in execute, allows population of fields before fetch()

2 files changed, 23 insertions, 17 deletions

diff --git a/libpqpp/selectcommand.cpp b/libpqpp/selectcommand.cpp
index 3798406..23be577 100644
--- a/libpqpp/selectcommand.cpp
+++ b/libpqpp/selectcommand.cpp
@@ -58,34 +58,39 @@ PQ::SelectCommand::execute()
 		}
 		c->beginTx();
 		txOpened = true;
-		c->checkResultFree(
+		c->checkResult(
 				PQexecParams(c->conn, psql.c_str(), values.size(), NULL, &values.front(), &lengths.front(), &formats.front(), 0),
 				PGRES_COMMAND_OK);
+		fetchTuples();
+		unsigned int nFields = PQnfields(execRes);
+		fields.resize(nFields);
+		for (unsigned int f = 0; f < nFields; f += 1) {
+			Column * c = new Column(this, f);
+			fields[f] = c;
+			fieldsName[c->name] = c;
+		}
 		executed = true;
 	}
 }
 
+void
+PQ::SelectCommand::fetchTuples()
+{
+	if (execRes) {
+		PQclear(execRes);
+	}
+	execRes = NULL;
+	execRes = c->checkResult(PQexec(c->conn, ("FETCH 35 IN " + stmntName).c_str()), PGRES_TUPLES_OK);
+	nTuples = PQntuples(execRes);
+	tuple = -1;
+}
+
 bool
 PQ::SelectCommand::fetch()
 {
 	execute();
 	if (tuple >= (nTuples - 1)) {
-		if (execRes) {
-			PQclear(execRes);
-		}
-		execRes = NULL;
-		execRes = c->checkResult(PQexec(c->conn, ("FETCH 35 IN " + stmntName).c_str()), PGRES_TUPLES_OK);
-		nTuples = PQntuples(execRes);
-		tuple = -1;
-	}
-	if (fields.empty()) {
-		unsigned int nFields = PQnfields(execRes);
-		fields.resize(nFields);
-		for (unsigned int f = 0; f < nFields; f += 1) {
-			Column * c = new Column(this, f);
-			fields[f] = c;
-			fieldsName[c->name] = c;
-		}
+		fetchTuples();
 	}
 	if (tuple++ < (nTuples - 1)) {
 		return true;
diff --git a/libpqpp/selectcommand.h b/libpqpp/selectcommand.h
index 507bf43..f4774d7 100644
--- a/libpqpp/selectcommand.h
+++ b/libpqpp/selectcommand.h
@@ -21,6 +21,7 @@ namespace PQ {
 			unsigned int columnCount() const;
 			unsigned int getOrdinal(const Glib::ustring&) const;
 		private:
+			void fetchTuples();
 			mutable bool executed;
 			mutable bool txOpened;
 			std::vector<Column *> fields;