The table inheritance works mostly

When a table has partitions or inheritance children these are listed as subnodes. A subnode can appear multiple times under different parents as postgresql supports inheriting multiple tables.

The sizes are still missing and maybe some things I have note verified yet are not correct.

pglablib/ui/catalog/tables/TableTreeBuilder.cpp

@@ -0,0 +1,89 @@
+#include "TableTreeBuilder.h"
+#include "catalog/PgInheritsContainer.h"
+#include "TableNode.h"
+#include <ranges>
+
+TableTreeBuilder::TableTreeBuilder(
+    const std::map<Oid, PgClass> &source,
+    const IFindParents &inheritance
+)
+: source(source)
+, inheritance(inheritance)
+{
+}
+
+std::shared_ptr<TableNode> TableTreeBuilder::Build()
+{
+    rootNode = std::make_shared<TableNode>();
+
+    // when childrens are ordered before there parents
+    // the parent will automatically be added first (recursively)
+    // processed nodes are tracked in the nodes member
+    for (auto && e : source | std::views::filter(
+        [this] (auto &e)
+        {
+            return processedNodes.count(e.first) == 0;
+        })
+    )
+    {
+        addNode(e.second);
+    }
+    AssignNodeIndexesAndParents(rootNode);
+    auto ret = rootNode;
+    resetState();
+    return ret;
+}
+
+void TableTreeBuilder::resetState()
+{
+    rootNode.reset();
+    processedNodes.clear();
+}
+
+std::shared_ptr<TableNode>  TableTreeBuilder::addNode(const PgClass &cls)
+{
+    std::shared_ptr<TableNode> node = std::make_shared<TableNode>(cls);
+    processedNodes.emplace(cls.oid(), node);
+    std::vector<Oid> parents = inheritance.getParentsOf(cls.oid());
+    if (parents.empty())
+        addToplevelNode(node);
+    else
+        addToParents(node, parents);
+    return node;
+}
+
+void TableTreeBuilder::addToplevelNode(std::shared_ptr<TableNode> node)
+{
+    rootNode->children.push_back(node);
+}
+
+void TableTreeBuilder::addToParents(std::shared_ptr<TableNode> node, const std::vector<Oid> &parents)
+{
+    for (auto &parent : parents)
+    {
+        getParent(parent)->children.push_back(node);
+    }
+}
+
+std::shared_ptr<TableNode> TableTreeBuilder::getParent(Oid oid)
+{
+    auto parent = processedNodes.find(oid);
+    if (parent != processedNodes.end())
+        return parent->second;
+
+    // Not present, find in source list and add now
+    auto source_iter = source.find(oid);
+    assert(source_iter != source.end());
+    return addNode(source_iter->second);
+}
+
+void TableTreeBuilder::AssignNodeIndexesAndParents(std::shared_ptr<TableNode> parent)
+{
+    int index = 0;
+    for (auto &n : parent->children)
+    {
+        n->parent = parent;
+        n->myIndex = index++;
+        AssignNodeIndexesAndParents(n);
+    }
+}