added more join_left methods to query_from_intermediate to write shorter fluent sql queries

src/sql/query_intermediates.cpp

@@ -85,7 +85,9 @@ query_order_direction_intermediate query_order_by_intermediate::desc()
 
 query_where_intermediate query_from_intermediate::where_clause(std::unique_ptr<basic_condition> &&cond)
 {
-  data_->parts.push_back(std::make_unique<query_where_part>(std::move(cond)));
+  if (cond) {
+    data_->parts.push_back(std::make_unique<query_where_part>(std::move(cond)));
+  }
   return {connection_, schema_, data_};
 }
 
@@ -113,30 +115,6 @@ query_order_by_intermediate query_where_intermediate::order_by(const column &col
   return {connection_, schema_, data_};
 }
 
-query_join_intermediate query_on_intermediate::join_left(const table &t)
-{
-  data_->parts.push_back(std::make_unique<query_join_part>(t));
-  return {connection_, schema_, data_};
-}
-
-query_where_intermediate query_on_intermediate::where_clause(std::unique_ptr<basic_condition> &&cond)
-{
-  data_->parts.push_back(std::make_unique<query_where_part>(std::move(cond)));
-  return {connection_, schema_, data_};
-}
-
-query_group_by_intermediate query_on_intermediate::group_by(const column &col)
-{
-  data_->parts.push_back(std::make_unique<query_group_by_part>(col));
-  return {connection_, schema_, data_};
-}
-
-query_order_by_intermediate query_on_intermediate::order_by(const column &col)
-{
-  data_->parts.push_back(std::make_unique<query_order_by_part>(col));
-  return {connection_, schema_, data_};
-}
-
 query_on_intermediate query_join_intermediate::on_clause(std::unique_ptr<basic_condition> &&cond)
 {
   data_->parts.push_back(std::make_unique<query_on_part>(std::move(cond)));
@@ -149,6 +127,22 @@ query_join_intermediate query_from_intermediate::join_left(const table &t)
   return {connection_, schema_, data_};
 }
 
+query_from_intermediate query_from_intermediate::join_left(join_data &data)
+{
+  data_->parts.push_back(std::make_unique<query_join_part>(data.join_table));
+  data_->parts.push_back(std::make_unique<query_on_part>(std::move(data.condition)));
+  return {connection_, schema_, data_};
+}
+
+query_from_intermediate query_from_intermediate::join_left(std::vector<join_data> &data_vector)
+{
+  for (auto &data : data_vector) {
+    data_->parts.push_back(std::make_unique<query_join_part>(data.join_table));
+    data_->parts.push_back(std::make_unique<query_on_part>(std::move(data.condition)));
+  }
+  return {connection_, schema_, data_};
+}
+
 query_select_intermediate::query_select_intermediate(connection &db, const sql::schema &schema, const std::vector<column>& columns)
 : query_start_intermediate(db, schema)
 {

src/sql/session.cpp

@@ -105,24 +105,13 @@ std::unique_ptr<query_result_impl> session::fetch(const std::string &sql) const
 
 query_select session::build_select_query(connection_ptr<connection> &conn, entity_query_data &&data) const
 {
-  auto q = conn->query(*schema_)
+  return conn->query(*schema_)
     .select(data.columns)
-    .from(data.root_table_name);
-
-  auto it = data.joins.begin();
-  if (it != data.joins.end()) {
-    auto qj = q.join_left(it->join_table).on(std::move(it->condition));
-    while (++it != data.joins.end()) {
-      qj.join_left(it->join_table).on(std::move(it->condition));
-    }
-    if (data.where_clause) {
-      return qj.where(std::move(data.where_clause));
-    }
-    return qj;
-  } else if (data.where_clause) {
-    return q.where(std::move(data.where_clause));
-  } else {
-    return q;
-  }
+    .from(data.root_table_name)
+    .join_left(data.joins)
+    .where(std::move(data.where_clause))
+    .order_by({data.root_table_name, data.pk_column_})
+    .asc();
 }
+
 }