diff --git a/src/AddRecordDialog.cpp b/src/AddRecordDialog.cpp
index f6784ee1..190d1c55 100644
--- a/src/AddRecordDialog.cpp
+++ b/src/AddRecordDialog.cpp
@@ -112,12 +112,12 @@ public:
     }
 };
 
-AddRecordDialog::AddRecordDialog(DBBrowserDB& db, const sqlb::ObjectIdentifier& tableName, QWidget* parent, const std::vector<std::string>& pseudo_pk)
+AddRecordDialog::AddRecordDialog(DBBrowserDB& db, const sqlb::ObjectIdentifier& tableName, QWidget* parent, const std::vector<std::string>& _pseudo_pk)
     : QDialog(parent),
       ui(new Ui::AddRecordDialog),
       pdb(db),
       curTable(tableName),
-      pseudo_pk(pseudo_pk)
+      pseudo_pk(_pseudo_pk)
 {
     // Create UI
     ui->setupUi(this);
diff --git a/src/CondFormat.cpp b/src/CondFormat.cpp
index 3b76bf80..1f963576 100644
--- a/src/CondFormat.cpp
+++ b/src/CondFormat.cpp
@@ -24,10 +24,10 @@ QString CondFormat::filterToSqlCondition(const QString& value, const QString& en
         int sepIdx = value.indexOf('~');
         val  = value.mid(0, sepIdx);
         val2 = value.mid(sepIdx+1);
-        val.toFloat(&ok);
+        float valf = val.toFloat(&ok);
         if (ok) {
-            val2.toFloat(&ok);
-            ok = ok && (val.toFloat() < val2.toFloat());
+            float val2f = val2.toFloat(&ok);
+            ok = ok && (valf < val2f);
         }
     }
     if (ok) {
diff --git a/src/EditDialog.cpp b/src/EditDialog.cpp
index e1279276..973d0e98 100644
--- a/src/EditDialog.cpp
+++ b/src/EditDialog.cpp
@@ -444,12 +444,12 @@ void EditDialog::updateApplyButton()
         ui->buttonApply->setEnabled(true);
 }
 
-bool EditDialog::promptInvalidData(const QString& dataType, const QString& errorString)
+bool EditDialog::promptInvalidData(const QString& data_type, const QString& errorString)
 {
     QMessageBox::StandardButton reply = QMessageBox::question(
       this,
       tr("Invalid data for this mode"),
-      tr("The cell contains invalid %1 data. Reason: %2. Do you really want to apply it to the cell?").arg(dataType, errorString),
+      tr("The cell contains invalid %1 data. Reason: %2. Do you really want to apply it to the cell?").arg(data_type, errorString),
       QMessageBox::Apply | QMessageBox::Cancel);
     return (reply == QMessageBox::Apply);
 }
diff --git a/src/EditDialog.h b/src/EditDialog.h
index b814d048..9b54a240 100644
--- a/src/EditDialog.h
+++ b/src/EditDialog.h
@@ -91,7 +91,7 @@ private:
 
     int checkDataType(const QByteArray& data);
     QString humanReadableSize(double byteCount) const;
-    bool promptInvalidData(const QString& dataType, const QString& errorString);
+    bool promptInvalidData(const QString& data_type, const QString& errorString);
     void setDataInBuffer(const QByteArray& data, DataSources source);
     void setStackCurrentIndex(int editMode);
 };
diff --git a/src/EditIndexDialog.cpp b/src/EditIndexDialog.cpp
index 467888f6..da041486 100644
--- a/src/EditIndexDialog.cpp
+++ b/src/EditIndexDialog.cpp
@@ -77,7 +77,7 @@ EditIndexDialog::EditIndexDialog(DBBrowserDB& db, const sqlb::ObjectIdentifier&
     connect(ui->tableIndexColumns, &QTableWidget::itemChanged,
             [=](QTableWidgetItem* item)
     {
-        index.fields[item->row()].setName(item->text().toStdString());
+        index.fields[static_cast<size_t>(item->row())].setName(item->text().toStdString());
         updateSqlText();
     });
 
@@ -156,7 +156,7 @@ void EditIndexDialog::updateColumnLists()
         if(indexFields.at(i).expression())
             flags |= Qt::ItemIsEditable;
         name->setFlags(flags);
-        ui->tableIndexColumns->setItem(i, 0, name);
+        ui->tableIndexColumns->setItem(static_cast<int>(i), 0, name);
 
         // And put a combobox to select the order in which to index the field in the last column
         QComboBox* order = new QComboBox(this);
@@ -164,7 +164,7 @@ void EditIndexDialog::updateColumnLists()
         order->addItem("ASC");
         order->addItem("DESC");
         order->setCurrentText(QString::fromStdString(indexFields.at(i).order()).toUpper());
-        ui->tableIndexColumns->setCellWidget(i, 1, order);
+        ui->tableIndexColumns->setCellWidget(static_cast<int>(i), 1, order);
         connect(order, &QComboBox::currentTextChanged,
                 [=](QString new_order)
         {
@@ -220,7 +220,7 @@ void EditIndexDialog::removeFromIndex(const QModelIndex& idx)
     // If this is an expression column and the action was triggered by a double click event instead of a button click,
     // we won't remove the expression column because it's too likely that this was only done by accident by the user.
     // Instead just open the expression column for editing.
-    if(index.fields[row].expression() && sender() != ui->buttonFromIndex)
+    if(index.fields[static_cast<size_t>(row)].expression() && sender() != ui->buttonFromIndex)
     {
         ui->tableIndexColumns->editItem(ui->tableIndexColumns->item(row, 0));
         return;
@@ -313,7 +313,7 @@ void EditIndexDialog::moveCurrentColumn(bool down)
         return;
 
     // Swap the columns
-    std::swap(index.fields[currentRow], index.fields[newRow]);
+    std::swap(index.fields[static_cast<size_t>(currentRow)], index.fields[static_cast<size_t>(newRow)]);
 
     // Update UI
     updateColumnLists();
@@ -326,7 +326,7 @@ void EditIndexDialog::addExpressionColumn()
 {
     // Check if there already is an empty expression column
     auto field_it = sqlb::findField(index, "");
-    int row = std::distance(index.fields.begin(), field_it);
+    int row = static_cast<int>(std::distance(index.fields.begin(), field_it));
     if(field_it == index.fields.end())
     {
         // There is no empty expression column yet, so add one.
diff --git a/src/EditTableDialog.cpp b/src/EditTableDialog.cpp
index 607cdae5..60e6ce96 100644
--- a/src/EditTableDialog.cpp
+++ b/src/EditTableDialog.cpp
@@ -331,8 +331,8 @@ bool EditTableDialog::eventFilter(QObject *object, QEvent *event)
 
 void EditTableDialog::itemChanged(QTreeWidgetItem *item, int column)
 {
-    int index = ui->treeWidget->indexOfTopLevelItem(item);
-    if(index < static_cast<int>(m_table.fields.size()))
+    size_t index = static_cast<size_t>(ui->treeWidget->indexOfTopLevelItem(item));
+    if(index < m_table.fields.size())
     {
         sqlb::Field& field = m_table.fields.at(index);
         QString oldFieldName = QString::fromStdString(field.name());
@@ -348,7 +348,7 @@ void EditTableDialog::itemChanged(QTreeWidgetItem *item, int column)
             // because it's doing a case-independent search and it can't return another field number because SQLite prohibits duplicate field
             // names (no matter the case). So when this happens we just allow the renaming because there's no harm to be expected from it.
             auto foundField = sqlb::findField(m_table, item->text(column).toStdString());
-            if(foundField != m_table.fields.end() && foundField-m_table.fields.begin() != index)
+            if(foundField != m_table.fields.end() && foundField-m_table.fields.begin() != static_cast<int>(index))
             {
                 QMessageBox::warning(this, qApp->applicationName(), tr("There already is a field with that name. Please rename it first or choose a different "
                                                                        "name for this field."));
@@ -741,7 +741,7 @@ void EditTableDialog::moveCurrentField(bool down)
     ui->treeWidget->setCurrentIndex(ui->treeWidget->currentIndex().sibling(newRow, 0));
 
     // Finally update the table SQL
-    std::swap(m_table.fields[newRow], m_table.fields[currentRow]);
+    std::swap(m_table.fields[static_cast<size_t>(newRow)], m_table.fields[static_cast<size_t>(currentRow)]);
 
     // Update the SQL preview
     updateSqlText();
diff --git a/src/ExportDataDialog.cpp b/src/ExportDataDialog.cpp
index c8dd5fb5..2ac0f66a 100644
--- a/src/ExportDataDialog.cpp
+++ b/src/ExportDataDialog.cpp
@@ -225,7 +225,7 @@ bool ExportDataDialog::exportQueryJson(const QString& sQuery, const QString& sFi
                 for(int i=0;i<columns;++i)
                 {
                     int type = sqlite3_column_type(stmt, i);
-                    std::string column_name = column_names[i];
+                    std::string column_name = column_names[static_cast<size_t>(i)];
 
                     switch (type) {
                     case SQLITE_INTEGER: {
diff --git a/src/ExtendedScintilla.cpp b/src/ExtendedScintilla.cpp
index a928185a..99ba8e86 100644
--- a/src/ExtendedScintilla.cpp
+++ b/src/ExtendedScintilla.cpp
@@ -88,7 +88,7 @@ ExtendedScintilla::~ExtendedScintilla()
 void ExtendedScintilla::updateLineNumberAreaWidth()
 {
     // Calculate number of digits of the current number of lines
-    int digits = std::floor(std::log10(lines())) + 1;
+    int digits = static_cast<int>(std::log10(lines())) + 1;
 
     // Calculate the width of this number if it was all zeros (this is because a 1 might require less space than a 0 and this could
     // cause some flickering depending on the font) and set the new margin width.
@@ -225,8 +225,8 @@ void ExtendedScintilla::setErrorIndicator(int position)
     // Set error indicator for the position until end of line, but only if they're enabled
     if(showErrorIndicators) {
 
-        int column = SendScintilla(QsciScintillaBase::SCI_GETCOLUMN, position);
-        int line = SendScintilla(QsciScintillaBase::SCI_LINEFROMPOSITION, position);
+        int column = static_cast<int>(SendScintilla(QsciScintillaBase::SCI_GETCOLUMN, position));
+        int line = static_cast<int>(SendScintilla(QsciScintillaBase::SCI_LINEFROMPOSITION, position));
 
         fillIndicatorRange(line, column, line+1, 0, errorIndicatorNumber);
     }
diff --git a/src/ExtendedTableWidget.cpp b/src/ExtendedTableWidget.cpp
index 62042592..9d62cf11 100644
--- a/src/ExtendedTableWidget.cpp
+++ b/src/ExtendedTableWidget.cpp
@@ -149,7 +149,7 @@ QWidget* ExtendedTableWidgetEditorDelegate::createEditor(QWidget* parent, const
 
         // if the current column of the current table does NOT have not-null constraint,
         // the NULL is united to the query to get the possible values in the combo-box.
-        if (!currentTable->fields.at(index.column()-1).notnull())
+        if (!currentTable->fields.at(static_cast<size_t>(index.column())-1).notnull())
             query.append (" UNION SELECT NULL");
 
         SqliteTableModel* fkModel = new SqliteTableModel(m->db(), parent, m->chunkSize(), m->encoding());
@@ -710,10 +710,11 @@ void ExtendedTableWidget::useAsFilter(const QString& filterOperator, bool binary
 
     // If binary operator, the cell data is used as first value and
     // the second value must be added by the user.
+    size_t column = static_cast<size_t>(index.column());
     if (binary)
-        m_tableHeader->setFilter(index.column(), value + filterOperator);
+        m_tableHeader->setFilter(column, value + filterOperator);
     else
-        m_tableHeader->setFilter(index.column(), filterOperator + value + operatorSuffix);
+        m_tableHeader->setFilter(column, filterOperator + value + operatorSuffix);
 }
 
 void ExtendedTableWidget::duplicateUpperCell()
@@ -995,7 +996,7 @@ void ExtendedTableWidget::sortByColumns(const std::vector<sqlb::SortedColumn>& c
     // Are we using a SqliteTableModel as a model? These support multiple sort columns. Other models might not; for those we just use the first sort column
     SqliteTableModel* sqlite_model = dynamic_cast<SqliteTableModel*>(model());
     if(sqlite_model == nullptr)
-        model()->sort(columns.front().column, columns.front().direction == sqlb::Ascending ? Qt::AscendingOrder : Qt::DescendingOrder);
+        model()->sort(static_cast<int>(columns.front().column), columns.front().direction == sqlb::Ascending ? Qt::AscendingOrder : Qt::DescendingOrder);
     else
         sqlite_model->sort(columns);
 }
diff --git a/src/FilterTableHeader.cpp b/src/FilterTableHeader.cpp
index 06592315..9e4d4bac 100644
--- a/src/FilterTableHeader.cpp
+++ b/src/FilterTableHeader.cpp
@@ -22,14 +22,14 @@ FilterTableHeader::FilterTableHeader(QTableView* parent) :
     setContextMenuPolicy(Qt::CustomContextMenu);
 }
 
-void FilterTableHeader::generateFilters(int number, bool showFirst)
+void FilterTableHeader::generateFilters(size_t number, bool showFirst)
 {
     // Delete all the current filter widgets
     qDeleteAll(filterWidgets);
     filterWidgets.clear();
 
     // And generate a bunch of new ones
-    for(int i=0;i < number; ++i)
+    for(size_t i=0;i < number; ++i)
     {
         FilterLineEdit* l = new FilterLineEdit(this, &filterWidgets, i);
         if(!showFirst && i == 0)        // This hides the first input widget which belongs to the hidden rowid column
diff --git a/src/FilterTableHeader.h b/src/FilterTableHeader.h
index 6dedcfbe..7b933099 100644
--- a/src/FilterTableHeader.h
+++ b/src/FilterTableHeader.h
@@ -18,7 +18,7 @@ public:
     bool hasFilters() const {return (filterWidgets.size() > 0);}
     
 public slots:
-    void generateFilters(int number, bool showFirst = false);
+    void generateFilters(size_t number, bool showFirst = false);
     void adjustPositions();
     void clearFilters();
     void setFilter(size_t column, const QString& value);
diff --git a/src/ImportCsvDialog.cpp b/src/ImportCsvDialog.cpp
index be56eea6..e859a0d0 100644
--- a/src/ImportCsvDialog.cpp
+++ b/src/ImportCsvDialog.cpp
@@ -4,6 +4,7 @@
 #include "csvparser.h"
 #include "sqlite.h"
 #include "Settings.h"
+#include "Data.h"
 
 #include <QMessageBox>
 #include <QProgressDialog>
@@ -42,10 +43,7 @@ ImportCsvDialog::ImportCsvDialog(const QStringList &filenames, DBBrowserDB* db,
     ui->editName->setText(file.baseName());
 
     // Create a list of all available encodings and create an auto completion list from them
-    QStringList encodingList;
-    for(const QByteArray& enc : QTextCodec::availableCodecs())
-        encodingList.push_back(enc);
-    encodingCompleter = new QCompleter(encodingList, this);
+    encodingCompleter = new QCompleter(toStringList(QTextCodec::availableCodecs()), this);
     encodingCompleter->setCaseSensitivity(Qt::CaseInsensitive);
     ui->editCustomEncoding->setCompleter(encodingCompleter);
 
@@ -125,7 +123,7 @@ void rollback(
 class CSVImportProgress : public CSVProgress
 {
 public:
-    explicit CSVImportProgress(unsigned long long filesize)
+    explicit CSVImportProgress(int64_t filesize)
         : totalFileSize(filesize)
     {
         m_pProgressDlg = new QProgressDialog(
@@ -136,6 +134,9 @@ public:
         m_pProgressDlg->setWindowModality(Qt::ApplicationModal);
     }
 
+    CSVImportProgress(const CSVImportProgress&) = delete;
+    bool operator=(const CSVImportProgress&) = delete;
+
     ~CSVImportProgress() override
     {
         delete m_pProgressDlg;
@@ -146,7 +147,7 @@ public:
         m_pProgressDlg->show();
     }
 
-    bool update(unsigned long long pos) override
+    bool update(int64_t pos) override
     {
         m_pProgressDlg->setValue(static_cast<int>((static_cast<float>(pos) / static_cast<float>(totalFileSize)) * 10000.0f));
         qApp->processEvents();
@@ -162,7 +163,7 @@ public:
 private:
     QProgressDialog* m_pProgressDlg;
 
-    unsigned long long totalFileSize;
+    int64_t totalFileSize;
 };
 
 void ImportCsvDialog::accept()
@@ -265,17 +266,17 @@ void ImportCsvDialog::updatePreview()
         {
             // Generate vertical header items
             if(i == 0)
-                ui->tablePreview->setVerticalHeaderItem(rowNum, new QTableWidgetItem(QString::number(rowNum + 1)));
+                ui->tablePreview->setVerticalHeaderItem(static_cast<int>(rowNum), new QTableWidgetItem(QString::number(rowNum + 1)));
 
             // Add table item. Limit data length to a maximum character count to avoid a sluggish UI. And it's very unlikely that this
             // many characters are going to be needed anyway for a preview.
-            int data_length = data.fields[i].data_length;
+            uint64_t data_length = data.fields[i].data_length;
             if(data_length > 1024)
                 data_length = 1024;
             ui->tablePreview->setItem(
-                        rowNum,
-                        i,
-                        new QTableWidgetItem(QString::fromUtf8(data.fields[i].data, data_length)));
+                        static_cast<int>(rowNum),
+                        static_cast<int>(i),
+                        new QTableWidgetItem(QString::fromUtf8(data.fields[i].data, static_cast<int>(data_length))));
         }
 
         return true;
@@ -401,7 +402,7 @@ sqlb::FieldVector ImportCsvDialog::generateFieldList(const QString& filename)
             if(rowNum == 0 && ui->checkboxHeader->isChecked())
             {
                 // Take field name from CSV and remove invalid characters
-                fieldname = QString::fromUtf8(data.fields[i].data, data.fields[i].data_length);
+                fieldname = QString::fromUtf8(data.fields[i].data, static_cast<int>(data.fields[i].data_length));
                 fieldname.replace("`", "");
                 fieldname.replace(" ", "");
                 fieldname.replace('"', "");
@@ -429,7 +430,7 @@ sqlb::FieldVector ImportCsvDialog::generateFieldList(const QString& filename)
                 std::string old_type = fieldList.at(i).type();
                 if(old_type != "TEXT")
                 {
-                    QString content = QString::fromUtf8(data.fields[i].data, data.fields[i].data_length);
+                    QString content = QString::fromUtf8(data.fields[i].data, static_cast<int>(data.fields[i].data_length));
 
                     // Check if the content can be converted to an integer or to float
                     bool convert_to_int, convert_to_float;
@@ -635,7 +636,7 @@ bool ImportCsvDialog::importCsv(const QString& fileName, const QString& name)
         {
             // Empty values need special treatment
             // When importing into an existing table where we could find out something about its table definition
-            if(importToExistingTable && data.fields[i].data_length == 0 && static_cast<size_t>(nullValues.size()) > i)
+            if(importToExistingTable && data.fields[i].data_length == 0 && nullValues.size() > i)
             {
                 // Do we want to fail when trying to import an empty value into this field? Then exit with an error.
                 if(failOnMissingFieldList.at(i))
@@ -644,13 +645,13 @@ bool ImportCsvDialog::importCsv(const QString& fileName, const QString& name)
                 // This is an empty value. We'll need to look up how to handle it depending on the field to be inserted into.
                 const QByteArray& val = nullValues.at(i);
                 if(!val.isNull())       // No need to bind NULL values here as that is the default bound value in SQLite
-                    sqlite3_bind_text(stmt, i+1, val, val.size(), SQLITE_STATIC);
+                    sqlite3_bind_text(stmt, static_cast<int>(i)+1, val, val.size(), SQLITE_STATIC);
             // When importing into a new table, use the missing values setting directly
             } else if(!importToExistingTable && data.fields[i].data_length == 0) {
                 // No need to bind NULL values here as that is the default bound value in SQLite
             } else {
                 // This is a non-empty value, or we want to insert the empty string. Just add it to the statement
-                sqlite3_bind_text(stmt, i+1, data.fields[i].data, data.fields[i].data_length, SQLITE_STATIC);
+                sqlite3_bind_text(stmt, static_cast<int>(i)+1, data.fields[i].data, static_cast<int>(data.fields[i].data_length), SQLITE_STATIC);
             }
         }
 
diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index ad50c184..65f76063 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -809,7 +809,7 @@ void MainWindow::populateTable()
             const sqlb::FieldInfoList& tablefields = db.getObjectByName(tablename)->fieldInformation();
             for(size_t i=0; i<tablefields.size(); ++i)
             {
-                QString format = storedData.displayFormats[i+1];
+                QString format = storedData.displayFormats[static_cast<int>(i)+1];
                 if(format.size())
                 {
                     query.selectedColumns().emplace_back(tablefields.at(i).name, format.toStdString());
@@ -884,7 +884,7 @@ void MainWindow::applyBrowseTableSettings(BrowseDataTableSettings storedData, bo
         FilterTableHeader* filterHeader = qobject_cast<FilterTableHeader*>(ui->dataTable->horizontalHeader());
         bool oldState = filterHeader->blockSignals(true);
         for(auto filterIt=storedData.filterValues.constBegin();filterIt!=storedData.filterValues.constEnd();++filterIt)
-            filterHeader->setFilter(filterIt.key(), filterIt.value());
+            filterHeader->setFilter(static_cast<size_t>(filterIt.key()), filterIt.value());
 
         // Conditional formats
         for(auto formatIt=storedData.condFormats.constBegin(); formatIt!=storedData.condFormats.constEnd(); ++formatIt)
@@ -3388,7 +3388,7 @@ void MainWindow::jumpToRow(const sqlb::ObjectIdentifier& table, QString column,
     populateTable();
 
     // Set filter
-    ui->dataTable->filterHeader()->setFilter(column_index-obj->fields.begin()+1, QString("=") + value);
+    ui->dataTable->filterHeader()->setFilter(static_cast<size_t>(column_index-obj->fields.begin()+1), QString("=") + value);
 }
 
 void MainWindow::showDataColumnPopupMenu(const QPoint& pos)
@@ -3460,9 +3460,9 @@ void MainWindow::editDataColumnDisplayFormat()
     int field_number = sender()->property("clicked_column").toInt();
     QString field_name;
     if (db.getObjectByName(current_table)->type() == sqlb::Object::Table)
-        field_name = QString::fromStdString(db.getObjectByName<sqlb::Table>(current_table)->fields.at(field_number-1).name());
+        field_name = QString::fromStdString(db.getObjectByName<sqlb::Table>(current_table)->fields.at(static_cast<size_t>(field_number)-1).name());
     else
-        field_name = QString::fromStdString(db.getObjectByName<sqlb::View>(current_table)->fieldNames().at(field_number-1));
+        field_name = QString::fromStdString(db.getObjectByName<sqlb::View>(current_table)->fieldNames().at(static_cast<size_t>(field_number)-1));
     // Get the current display format of the field
     QString current_displayformat = browseTableSettings[current_table].displayFormats[field_number];
 
@@ -3512,7 +3512,7 @@ void MainWindow::showRowidColumn(bool show, bool skipFilters)
 
     // Update the filter row
     if(!skipFilters)
-        qobject_cast<FilterTableHeader*>(ui->dataTable->horizontalHeader())->generateFilters(m_browseTableModel->columnCount(), show);
+        qobject_cast<FilterTableHeader*>(ui->dataTable->horizontalHeader())->generateFilters(static_cast<size_t>(m_browseTableModel->columnCount()), show);
 
     // Re-enable signals
     ui->dataTable->horizontalHeader()->blockSignals(false);
diff --git a/src/PlotDock.cpp b/src/PlotDock.cpp
index 7878436e..9ca338e9 100644
--- a/src/PlotDock.cpp
+++ b/src/PlotDock.cpp
@@ -318,7 +318,7 @@ void PlotDock::updatePlot(SqliteTableModel* model, BrowseDataTableSettings* sett
                     case QVariant::Date: {
                         QString s = model->data(model->index(j, x)).toString();
                         QDateTime d = QDateTime::fromString(s, Qt::ISODate);
-                        xdata[j] = d.toMSecsSinceEpoch() / 1000.0;
+                        xdata[j] = static_cast<double>(d.toMSecsSinceEpoch()) / 1000.0;
                         break;
                     }
                     case QVariant::Time: {
diff --git a/src/RemoteDatabase.cpp b/src/RemoteDatabase.cpp
index 63c2818e..74b75588 100644
--- a/src/RemoteDatabase.cpp
+++ b/src/RemoteDatabase.cpp
@@ -256,15 +256,7 @@ void RemoteDatabase::gotReply(QNetworkReply* reply)
 void RemoteDatabase::gotError(QNetworkReply* reply, const QList<QSslError>& errors)
 {
     // Are there any errors in here that aren't about self-signed certificates and non-matching hostnames?
-    bool serious_errors = false;
-    for(const QSslError& error : errors)
-    {
-        if(error.error() != QSslError::SelfSignedCertificate)
-        {
-            serious_errors = true;
-            break;
-        }
-    }
+    bool serious_errors = std::any_of(errors.begin(), errors.end(), [](const QSslError& error) { return error.error() != QSslError::SelfSignedCertificate; });
 
     // Just stop the error checking here and accept the reply if there were no 'serious' errors
     if(!serious_errors)
diff --git a/src/RemoteModel.cpp b/src/RemoteModel.cpp
index 1e7ac605..4a851f08 100644
--- a/src/RemoteModel.cpp
+++ b/src/RemoteModel.cpp
@@ -233,7 +233,7 @@ QVariant RemoteModel::data(const QModelIndex& index, int role) const
                     return QVariant();
 
                 // Convert size to human readable format
-                float size = item->value(RemoteModelColumnSize).toLongLong();
+                float size = item->value(RemoteModelColumnSize).toFloat();
                 QStringList list;
                 list << "KiB" << "MiB" << "GiB" << "TiB";
                 QStringListIterator it(list);
diff --git a/src/RowLoader.cpp b/src/RowLoader.cpp
index ecfec6eb..4f9cb61e 100644
--- a/src/RowLoader.cpp
+++ b/src/RowLoader.cpp
@@ -59,7 +59,7 @@ void RowLoader::triggerRowCountDetermination(int token)
         if(nrows >= 0)
             emit rowCountComplete(token, nrows);
 
-        std::lock_guard<std::mutex> lk(m);
+        std::lock_guard<std::mutex> lk2(m);
         nosync_taskDone();
     });
 }
diff --git a/src/RunSql.cpp b/src/RunSql.cpp
index 1b848a37..a5a91210 100644
--- a/src/RunSql.cpp
+++ b/src/RunSql.cpp
@@ -149,7 +149,7 @@ bool RunSql::executeNextStatement()
     int sql3status = sqlite3_prepare_v2(pDb.get(), tail, tail_length, &vm, &tail);
     QString queryPart = QString::fromUtf8(qbegin, static_cast<int>(tail - qbegin));
     int tail_length_before = tail_length;
-    tail_length -= (tail - qbegin);
+    tail_length -= static_cast<int>(tail - qbegin);
     int end_of_current_statement_position = execute_current_position + tail_length_before - tail_length;
 
     // Save remaining statements
diff --git a/src/csvparser.cpp b/src/csvparser.cpp
index 019a4ef2..82b54ca2 100644
--- a/src/csvparser.cpp
+++ b/src/csvparser.cpp
@@ -140,7 +140,7 @@ CSVParser::ParserResult CSVParser::parse(csvRowFunction insertFunction, QTextStr
     };
     FieldBufferDealloc dealloc(record);
 
-    qint64 bufferPos = 0;
+    int64_t bufferPos = 0;
     while(!stream.atEnd())
     {
         sBuffer = stream.read(m_nBufferSize).toUtf8();
diff --git a/src/csvparser.h b/src/csvparser.h
index 3547b2e7..38d3a44b 100644
--- a/src/csvparser.h
+++ b/src/csvparser.h
@@ -18,7 +18,7 @@ public:
     virtual ~CSVProgress() { }
 
     virtual void start() = 0;
-    virtual bool update(unsigned long long pos) = 0;
+    virtual bool update(int64_t pos) = 0;
     virtual void end() = 0;
 };
 
@@ -88,7 +88,7 @@ private:
     char m_cQuoteChar;
     CSVProgress* m_pCSVProgress;
 
-    unsigned long m_nBufferSize;        //! internal buffer read size
+    int64_t m_nBufferSize;        //! internal buffer read size
 };
 
 #endif
diff --git a/src/sqlitedb.cpp b/src/sqlitedb.cpp
index 410c3cab..a3c39012 100644
--- a/src/sqlitedb.cpp
+++ b/src/sqlitedb.cpp
@@ -57,16 +57,16 @@ int collCompare(void* /*pArg*/, int sizeA, const void* sA, int sizeB, const void
 
 static int sqlite_compare_utf16( void* /*arg*/,int size1, const void *str1, int size2, const void* str2)
 {
-    const QString string1 = QString::fromRawData(reinterpret_cast<const QChar*>(str1), size1 / sizeof(QChar));
-    const QString string2 = QString::fromRawData(reinterpret_cast<const QChar*>(str2), size2 / sizeof(QChar));
+    const QString string1 = QString::fromRawData(reinterpret_cast<const QChar*>(str1), static_cast<int>(static_cast<size_t>(size1) / sizeof(QChar)));
+    const QString string2 = QString::fromRawData(reinterpret_cast<const QChar*>(str2), static_cast<int>(static_cast<size_t>(size2) / sizeof(QChar)));
 
     return QString::compare(string1, string2, Qt::CaseSensitive);
 }
 
 static int sqlite_compare_utf16ci( void* /*arg*/,int size1, const void *str1, int size2, const void* str2)
 {
-    const QString string1 = QString::fromRawData(reinterpret_cast<const QChar*>(str1), size1 / sizeof(QChar));
-    const QString string2 = QString::fromRawData(reinterpret_cast<const QChar*>(str2), size2 / sizeof(QChar));
+    const QString string1 = QString::fromRawData(reinterpret_cast<const QChar*>(str1), static_cast<int>(static_cast<size_t>(size1) / sizeof(QChar)));
+    const QString string2 = QString::fromRawData(reinterpret_cast<const QChar*>(str2), static_cast<int>(static_cast<size_t>(size2) / sizeof(QChar)));
 
     return QString::compare(string1, string2, Qt::CaseInsensitive);
 }
@@ -81,7 +81,7 @@ static void sqlite_make_single_value(sqlite3_context* ctx, int num_arguments, sq
     char* output_str = new char[output.size()+1];
     std::strcpy(output_str, output.c_str());
 
-    sqlite3_result_text(ctx, output_str, output.length(), [](void* ptr) {
+    sqlite3_result_text(ctx, output_str, static_cast<int>(output.length()), [](void* ptr) {
         char* cptr = static_cast<char*>(ptr);
         delete cptr;
     });
diff --git a/src/sqlitetablemodel.cpp b/src/sqlitetablemodel.cpp
index 50f2b0f3..f4a3cb4b 100644
--- a/src/sqlitetablemodel.cpp
+++ b/src/sqlitetablemodel.cpp
@@ -66,7 +66,7 @@ void SqliteTableModel::handleFinishedFetch (int life_id, unsigned int fetched_ro
 
     if(new_row_count != old_row_count)
     {
-        beginInsertRows(QModelIndex(), old_row_count, new_row_count - 1);
+        beginInsertRows(QModelIndex(), static_cast<int>(old_row_count), static_cast<int>(new_row_count - 1));
         m_currentRowCount = new_row_count;
         endInsertRows();
     }
@@ -75,13 +75,13 @@ void SqliteTableModel::handleFinishedFetch (int life_id, unsigned int fetched_ro
     {
         // TODO optimize
         size_t num_columns = m_headers.size();
-        emit dataChanged(createIndex(fetched_row_begin, 0), createIndex(fetched_row_end - 1, num_columns - 1));
+        emit dataChanged(createIndex(static_cast<int>(fetched_row_begin), 0), createIndex(static_cast<int>(fetched_row_end) - 1, static_cast<int>(num_columns) - 1));
     }
 
     if(m_rowCountAvailable != RowCount::Complete)
         m_rowCountAvailable = RowCount::Partial;
 
-    emit finishedFetch(fetched_row_begin, fetched_row_end);
+    emit finishedFetch(static_cast<int>(fetched_row_begin), static_cast<int>(fetched_row_end));
 }
 
 void SqliteTableModel::handleRowCountComplete (int life_id, int num_rows)
@@ -90,7 +90,7 @@ void SqliteTableModel::handleRowCountComplete (int life_id, int num_rows)
         return;
 
     m_rowCountAvailable = RowCount::Complete;
-    handleFinishedFetch(life_id, num_rows, num_rows);
+    handleFinishedFetch(life_id, static_cast<unsigned int>(num_rows), static_cast<unsigned int>(num_rows));
 
     emit finishedRowCount();
 }
@@ -299,9 +299,11 @@ QVariant SqliteTableModel::data(const QModelIndex &index, int role) const
     bool row_available;
 
     const Row * cached_row;
-    if(m_cache.count(index.row()))
+    const size_t row = static_cast<size_t>(index.row());
+    const size_t column = static_cast<size_t>(index.column());
+    if(m_cache.count(row))
     {
-        cached_row = &m_cache.at(index.row());
+        cached_row = &m_cache.at(row);
         row_available = true;
     } else {
         blank_data = makeDefaultCacheEntry();
@@ -313,14 +315,14 @@ QVariant SqliteTableModel::data(const QModelIndex &index, int role) const
     {
         if(!row_available)
             return tr("loading...");
-        if(role == Qt::DisplayRole && cached_row->at(index.column()).isNull())
+        if(role == Qt::DisplayRole && cached_row->at(column).isNull())
         {
             return Settings::getValue("databrowser", "null_text").toString();
         } else if(role == Qt::DisplayRole && nosync_isBinary(index)) {
             return Settings::getValue("databrowser", "blob_text").toString();
         } else if(role == Qt::DisplayRole) {
             int limit = Settings::getValue("databrowser", "symbol_limit").toInt();
-            QByteArray displayText = cached_row->at(index.column());
+            QByteArray displayText = cached_row->at(column);
             if (displayText.length() > limit) {
                 // Add "..." to the end of truncated strings
                 return decode(displayText.left(limit).append(" ..."));
@@ -328,22 +330,22 @@ QVariant SqliteTableModel::data(const QModelIndex &index, int role) const
                 return decode(displayText);
             }
         } else {
-            return decode(cached_row->at(index.column()));
+            return decode(cached_row->at(column));
         }
     } else if(role == Qt::FontRole) {
         QFont font;
-        if(!row_available || cached_row->at(index.column()).isNull() || nosync_isBinary(index))
+        if(!row_available || cached_row->at(column).isNull() || nosync_isBinary(index))
             font.setItalic(true);
         return font;
     } else if(role == Qt::ForegroundRole) {
         if(!row_available)
             return QColor(100, 100, 100);
-        if(cached_row->at(index.column()).isNull())
+        if(cached_row->at(column).isNull())
             return QColor(Settings::getValue("databrowser", "null_fg_colour").toString());
         else if (nosync_isBinary(index))
             return QColor(Settings::getValue("databrowser", "bin_fg_colour").toString());
         else if (m_mCondFormats.contains(index.column())) {
-            QString value = cached_row->at(index.column());
+            QString value = cached_row->at(column);
             // Unlock before querying from DB
             lock.unlock();
             QColor condFormatColor = getMatchingCondFormatColor(index.column(), value, role);
@@ -355,12 +357,12 @@ QVariant SqliteTableModel::data(const QModelIndex &index, int role) const
     } else if (role == Qt::BackgroundRole) {
         if(!row_available)
             return QColor(255, 200, 200);
-        if(cached_row->at(index.column()).isNull())
+        if(cached_row->at(column).isNull())
             return QColor(Settings::getValue("databrowser", "null_bg_colour").toString());
         else if (nosync_isBinary(index))
             return QColor(Settings::getValue("databrowser", "bin_bg_colour").toString());
         else if (m_mCondFormats.contains(index.column())) {
-            QString value = cached_row->at(index.column());
+            QString value = cached_row->at(column);
             // Unlock before querying from DB
             lock.unlock();
             QColor condFormatColor = getMatchingCondFormatColor(index.column(), value, role);
@@ -406,7 +408,7 @@ sqlb::ForeignKeyClause SqliteTableModel::getForeignKeyClause(int column) const
         // Note that the rowid column has number -1 here, it can safely be excluded since there will never be a
         // foreign key on that column.
 
-        sqlb::ConstraintPtr ptr = tbl->constraint({tbl->fields.at(column).name()}, sqlb::Constraint::ForeignKeyConstraintType);
+        sqlb::ConstraintPtr ptr = tbl->constraint({tbl->fields.at(static_cast<size_t>(column)).name()}, sqlb::Constraint::ForeignKeyConstraintType);
         if(ptr)
             return *(std::dynamic_pointer_cast<sqlb::ForeignKeyClause>(ptr));
     }
@@ -436,10 +438,11 @@ bool SqliteTableModel::setTypedData(const QModelIndex& index, bool isBlob, const
     {
         QMutexLocker lock(&m_mutexDataCache);
 
-        auto & cached_row = m_cache.at(index.row());
+        auto & cached_row = m_cache.at(static_cast<size_t>(index.row()));
+        const size_t column = static_cast<size_t>(index.column());
 
         QByteArray newValue = encode(value.toByteArray());
-        QByteArray oldValue = cached_row.at(index.column());
+        QByteArray oldValue = cached_row.at(column);
 
         // Special handling for integer columns: instead of setting an integer column to an empty string, set it to '0' when it is also
         // used in a primary key. Otherwise SQLite will always output an 'datatype mismatch' error.
@@ -448,7 +451,7 @@ bool SqliteTableModel::setTypedData(const QModelIndex& index, bool isBlob, const
             sqlb::TablePtr table = m_db.getObjectByName<sqlb::Table>(m_query.table());
             if(table)
             {
-                auto field = sqlb::findField(table, m_headers.at(index.column()));
+                auto field = sqlb::findField(table, m_headers.at(column));
                 if(contains(table->primaryKey(), field->name()) && field->isInteger())
                     newValue = "0";
             }
@@ -459,10 +462,10 @@ bool SqliteTableModel::setTypedData(const QModelIndex& index, bool isBlob, const
         if(oldValue == newValue && oldValue.isNull() == newValue.isNull())
             return true;
 
-        if(m_db.updateRecord(m_query.table(), m_headers.at(index.column()), cached_row.at(0), newValue, isBlob, m_query.rowIdColumns()))
+        if(m_db.updateRecord(m_query.table(), m_headers.at(column), cached_row.at(0), newValue, isBlob, m_query.rowIdColumns()))
         {
-            cached_row[index.column()] = newValue;
-            if(m_headers.at(index.column()) == sqlb::joinStringVector(m_query.rowIdColumns(), ",")) {
+            cached_row[column] = newValue;
+            if(m_headers.at(column) == sqlb::joinStringVector(m_query.rowIdColumns(), ",")) {
                 cached_row[0] =  newValue;
                 const QModelIndex& rowidIndex = index.sibling(index.row(), 0);
                 lock.unlock();
@@ -494,7 +497,7 @@ Qt::ItemFlags SqliteTableModel::flags(const QModelIndex& index) const
     if(m_query.selectedColumns().size())
     {
         if(index.column() > 0)
-            custom_display_format = QString::fromStdString(m_query.selectedColumns().at(index.column()-1).selector) != sqlb::escapeIdentifier(headerData(index.column(), Qt::Horizontal).toString());
+            custom_display_format = QString::fromStdString(m_query.selectedColumns().at(static_cast<size_t>(index.column())-1).selector) != sqlb::escapeIdentifier(headerData(index.column(), Qt::Horizontal).toString());
     }
 
     if(!isBinary(index) && !custom_display_format)
@@ -574,9 +577,9 @@ bool SqliteTableModel::insertRows(int row, int count, const QModelIndex& parent)
     }
 
     beginInsertRows(parent, row, row + count - 1);
-    for(unsigned int i = 0; i < tempList.size(); ++i)
+    for(size_t i = 0; i < tempList.size(); ++i)
     {
-        m_cache.insert(i + row, std::move(tempList.at(i)));
+        m_cache.insert(i + static_cast<size_t>(row), std::move(tempList.at(i)));
         m_currentRowCount++;
     }
     endInsertRows();
@@ -597,8 +600,8 @@ bool SqliteTableModel::removeRows(int row, int count, const QModelIndex& parent)
     QStringList rowids;
     for(int i=count-1;i>=0;i--)
     {
-        if(m_cache.count(row+i)) {
-            rowids.append(m_cache.at(row + i).at(0));
+        if(m_cache.count(static_cast<size_t>(row+i))) {
+            rowids.append(m_cache.at(static_cast<size_t>(row + i)).at(0));
         }
     }
 
@@ -609,7 +612,7 @@ bool SqliteTableModel::removeRows(int row, int count, const QModelIndex& parent)
 
         for(int i=count-1;i>=0;i--)
         {
-            m_cache.erase(row + i);
+            m_cache.erase(static_cast<size_t>(row + i));
             m_currentRowCount--;
         }
 
@@ -626,7 +629,7 @@ QModelIndex SqliteTableModel::dittoRecord(int old_row)
     if (!insertRow(rowCount()))
         return QModelIndex();
 
-    int firstEditedColumn = 0;
+    size_t firstEditedColumn = 0;
     int new_row = rowCount() - 1;
 
     sqlb::TablePtr t = m_db.getObjectByName<sqlb::Table>(m_query.table());
@@ -637,12 +640,12 @@ QModelIndex SqliteTableModel::dittoRecord(int old_row)
             if (!firstEditedColumn)
                 firstEditedColumn = col + 1;
 
-            QVariant value = data(index(old_row, col + 1), Qt::EditRole);
-            setData(index(new_row, col + 1), value);
+            QVariant value = data(index(old_row, static_cast<int>(col + 1)), Qt::EditRole);
+            setData(index(new_row, static_cast<int>(col + 1)), value);
         }
     }
 
-    return index(new_row, firstEditedColumn);
+    return index(new_row, static_cast<int>(firstEditedColumn));
 }
 
 void SqliteTableModel::buildQuery()
@@ -756,9 +759,9 @@ void SqliteTableModel::updateFilter(int column, const QString& value)
 
     // If the value was set to an empty string remove any filter for this column. Otherwise insert a new filter rule or replace the old one if there is already one
     if(whereClause.isEmpty())
-        m_query.where().erase(column);
+        m_query.where().erase(static_cast<size_t>(column));
     else
-        m_query.where()[column] = whereClause.toStdString();
+        m_query.where()[static_cast<size_t>(column)] = whereClause.toStdString();
 
     // Build the new query
     buildQuery();
@@ -775,7 +778,7 @@ void SqliteTableModel::clearCache()
 
     if(m_currentRowCount > 0)
     {
-        beginRemoveRows(QModelIndex(), 0, m_currentRowCount - 1);
+        beginRemoveRows(QModelIndex(), 0, static_cast<int>(m_currentRowCount - 1));
         endRemoveRows();
     }
 
@@ -792,12 +795,13 @@ bool SqliteTableModel::isBinary(const QModelIndex& index) const
 
 bool SqliteTableModel::nosync_isBinary(const QModelIndex& index) const
 {
-    if(!m_cache.count(index.row()))
+    const size_t row = static_cast<size_t>(index.row());
+    if(!m_cache.count(row))
         return false;
 
-    const auto & cached_row = m_cache.at(index.row());
+    const auto & cached_row = m_cache.at(row);
 
-    return !isTextOnly(cached_row.at(index.column()), m_encoding, true);
+    return !isTextOnly(cached_row.at(static_cast<size_t>(index.column())), m_encoding, true);
 }
 
 QByteArray SqliteTableModel::encode(const QByteArray& str) const