Don't query foreign key settings repeatedly in Edit Table dialog

When changing the table name in the Edit Table dialog, don't query the
foreign key pragma for every key stroke.

See issue #1130.

src/EditTableDialog.cpp

@@ -56,6 +56,9 @@ EditTableDialog::EditTableDialog(DBBrowserDB& db, const sqlb::ObjectIdentifier&
     // And create a savepoint
     pdb.setSavepoint(m_sRestorePointName);
 
+    // Check now if foreign keys are enabled so we don't have to query this later again and again
+    m_bForeignKeysEnabled = (pdb.getPragma("foreign_keys") == "1");
+
     // Update UI
     ui->editTableName->setText(curTable.name());
     updateColumnWidth();
@@ -206,8 +209,6 @@ void EditTableDialog::checkInput()
         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) {
@@ -215,7 +216,7 @@ void EditTableDialog::checkInput()
             if(!fk.isNull()) {
                 if (oldTableName == fk->table()) {
                     fk->setTable(normTableName);
-                    if(!fksEnabled)
+                    if(!m_bForeignKeysEnabled)
                         pdb.renameColumn(curTable, m_table, f->name(), f, 0);
                 }
             }

src/EditTableDialog.h

@@ -69,6 +69,7 @@ private:
     QStringList fields;
     bool m_bNewTable;
     QString m_sRestorePointName;
+    bool m_bForeignKeysEnabled;
 };
 
 #endif