Support foreign key constraints referring to the same table (#933)

src/EditTableDialog.cpp

@@ -26,7 +26,9 @@ EditTableDialog::EditTableDialog(DBBrowserDB& db, const QString& tableName, bool
     connect(ui->treeWidget, SIGNAL(itemChanged(QTreeWidgetItem*,int)),this,SLOT(itemChanged(QTreeWidgetItem*,int)));
 
     // Set item delegate for foreign key column
-    ui->treeWidget->setItemDelegateForColumn(kForeignKey, new ForeignKeyEditorDelegate(db, m_table, this));
+    m_fkEditorDelegate = new ForeignKeyEditorDelegate(db, m_table, this);
+    ui->treeWidget->setItemDelegateForColumn(kForeignKey, m_fkEditorDelegate);
+
     // Editing an existing table?
     if(m_bNewTable == false)
     {
@@ -194,7 +196,29 @@ void EditTableDialog::checkInput()
         valid = false;
     if(ui->treeWidget->topLevelItemCount() == 0)
         valid = false;
-    m_table.setName(normTableName);
+    if (normTableName != m_table.name()) {
+        const QString oldTableName = m_table.name();
+        m_table.setName(normTableName);
+        m_fkEditorDelegate->updateTablesList(oldTableName);
+
+        bool fksEnabled = (pdb.getPragma("foreign_keys") == "1");
+
+        // update fk's that refer to table itself recursively
+        sqlb::FieldVector fields = m_table.fields();
+        foreach(sqlb::FieldPtr f, fields) {
+            QSharedPointer<sqlb::ForeignKeyClause> fk = m_table.constraint({f}, sqlb::Constraint::ForeignKeyConstraintType).dynamicCast<sqlb::ForeignKeyClause>();
+            if(!fk.isNull()) {
+                if (oldTableName == fk->table()) {
+                    fk->setTable(normTableName);
+                    if(!fksEnabled)
+                        pdb.renameColumn(curTable, m_table, f->name(), f, 0);
+                }
+            }
+        }
+
+        populateFields();
+    }
+
     updateSqlText();
     ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(valid);
 }

src/EditTableDialog.h

@@ -7,6 +7,7 @@
 
 class DBBrowserDB;
 class QTreeWidgetItem;
+class ForeignKeyEditorDelegate;
 
 namespace Ui {
 class EditTableDialog;
@@ -61,6 +62,7 @@ private slots:
 private:
     Ui::EditTableDialog* ui;
     DBBrowserDB& pdb;
+    ForeignKeyEditorDelegate* m_fkEditorDelegate;
     QString curTable;
     sqlb::Table m_table;
     QStringList types;

src/ForeignKeyEditorDelegate.cpp

@@ -78,7 +78,13 @@ ForeignKeyEditorDelegate::ForeignKeyEditorDelegate(const DBBrowserDB& db, sqlb::
     , m_db(db)
     , m_table(table)
 {
-
+    const auto objects = m_db.getBrowsableObjects();
+    for (auto obj : objects) {
+        if ("table" == obj.gettype()) {
+            QString tableName = obj.table.name();
+            m_tablesIds.insert(tableName, obj.table.fieldNames());
+        }
+    }
 }
 
 QWidget* ForeignKeyEditorDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const
@@ -99,6 +105,9 @@ QWidget* ForeignKeyEditorDelegate::createEditor(QWidget* parent, const QStyleOpt
         box->setCurrentIndex(0);
     });
 
+    editor->tablesComboBox->clear();
+    editor->tablesComboBox->addItems(m_tablesIds.keys());
+
     return editor;
 }
 
@@ -106,17 +115,6 @@ void ForeignKeyEditorDelegate::setEditorData(QWidget* editor, const QModelIndex&
 {
     ForeignKeyEditor* fkEditor = static_cast<ForeignKeyEditor*>(editor);
 
-    m_tablesIds.clear();
-    const auto objects = m_db.getBrowsableObjects();
-    for (auto obj : objects) {
-        if ("table" == obj.gettype()) {
-            QString tableName = obj.table.name();
-            m_tablesIds.insert(tableName, obj.table.fieldNames());
-        }
-    }
-
-    fkEditor->tablesComboBox->addItems(m_tablesIds.keys());
-
     int column = index.row(); // weird? I know right
     sqlb::FieldPtr field = m_table.fields().at(column);
     QSharedPointer<sqlb::ForeignKeyClause> fk = m_table.constraint({field}, sqlb::Constraint::ForeignKeyConstraintType).dynamicCast<sqlb::ForeignKeyClause>();
@@ -170,4 +168,12 @@ void ForeignKeyEditorDelegate::updateEditorGeometry(QWidget* editor, const QStyl
     editor->setGeometry(option.rect);
 }
 
+void ForeignKeyEditorDelegate::updateTablesList(const QString& oldTableName)
+{
+    // this is used for recursive table constraints when
+    // table column references column within same table
+    m_tablesIds.remove(oldTableName);
+    m_tablesIds.insert(m_table.name(), m_table.fieldNames());
+}
+
 #include "ForeignKeyEditorDelegate.moc"

src/ForeignKeyEditorDelegate.h

@@ -25,6 +25,8 @@ public:
     void setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const Q_DECL_OVERRIDE;
     void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE;
 
+    void updateTablesList(const QString& oldTableName);
+
 private:
     const DBBrowserDB& m_db;
     sqlb::Table& m_table;