finished postgres fetch

backends/postgres/src/postgres_result_reader.cpp

@@ -24,7 +24,7 @@ size_t postgres_result_reader::column_count() const
 
 const char *postgres_result_reader::column(size_t index) const
 {
-  return nullptr;
+  return PQgetvalue(result_, static_cast<int>(row_index_), static_cast<int>(index));
 }
 
 bool postgres_result_reader::fetch()
@@ -99,22 +99,39 @@ void postgres_result_reader::read_value(const char *id, size_t index, double &va
 
 void postgres_result_reader::read_value(const char *id, size_t index, char *value, size_t s)
 {
+  auto *val = PQgetvalue(result_, static_cast<int>(row_index_), static_cast<int>(index));
 
+  size_t len = strlen(value);
+  if (len > (size_t)s) {
+#ifdef _MSC_VER
+    strncpy_s(val, s, value, s);
+#else
+    strncpy(val, value, s);
+#endif
+    val[s-1] = '\n';
+  } else {
+#ifdef _MSC_VER
+    strcpy_s(val, s, value);
+#else
+    strcpy(val, value);
+#endif
+  }
 }
 
 void postgres_result_reader::read_value(const char *id, size_t index, std::string &value)
 {
-
+  auto *val = PQgetvalue(result_, static_cast<int>(row_index_), static_cast<int>(index));
+  if (strlen(val) != 0) {
+    value.assign(val);
+  }
 }
 
 void postgres_result_reader::read_value(const char *id, size_t index, std::string &value, size_t s)
 {
-
+  auto *val = PQgetvalue(result_, static_cast<int>(row_index_), static_cast<int>(index));
+  if (strlen(val) != 0) {
+    value.assign(val);
+  }
 }
 
-void postgres_result_reader::read_value(const char *id, size_t index, sql::any_type &value, sql::data_type_t type,
-                                        size_t size)
-{
-
-}
 }