Issue 18: Added a popup to modify table columns (#31)

Added a new popup to modify the columns of the table. With this new popup, the user can:

- Show and hide columns
- Move columns around
- Add new columns which are derived from the value of an expression
- Delete columns

Also got the overlay mechanisms working.

cmd/dynamo-browse/main.go

@@ -22,6 +22,7 @@ import (
 	"github.com/lmika/audax/internal/dynamo-browse/ui"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/keybindings"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/styles"
+	bus "github.com/lmika/events"
 	"github.com/lmika/gopkgs/cli"
 	"log"
 	"net"
@@ -72,6 +73,8 @@ func main() {
 		dynamoClient = dynamodb.NewFromConfig(cfg)
 	}
 
+	eventBus := bus.New()
+
 	uiStyles := styles.DefaultStyles
 	dynamoProvider := dynamo.NewProvider(dynamoClient)
 	resultSetSnapshotStore := workspacestore.NewResultSetSnapshotStore(ws)
@@ -93,8 +96,10 @@ func main() {
 	itemRendererService := itemrenderer.NewService(uiStyles.ItemView.FieldType, uiStyles.ItemView.MetaInfo)
 
 	state := controllers.NewState()
-	tableReadController := controllers.NewTableReadController(state, tableService, workspaceService, itemRendererService, *flagTable, true)
+	tableReadController := controllers.NewTableReadController(state, tableService, workspaceService, itemRendererService, eventBus, *flagTable)
 	tableWriteController := controllers.NewTableWriteController(state, tableService, tableReadController, settingStore)
+	columnsController := controllers.NewColumnsController(eventBus)
+	exportController := controllers.NewExportController(state, columnsController)
 	settingsController := controllers.NewSettingsController(settingStore)
 	keyBindings := keybindings.Default()
 
@@ -106,6 +111,8 @@ func main() {
 	model := ui.NewModel(
 		tableReadController,
 		tableWriteController,
+		columnsController,
+		exportController,
 		settingsController,
 		itemRendererService,
 		commandController,

internal/common/ui/events/commands.go

@@ -16,6 +16,12 @@ func SetStatus(msg string) tea.Cmd {
 	}
 }
 
+func SetTeaMessage(event tea.Msg) tea.Cmd {
+	return func() tea.Msg {
+		return event
+	}
+}
+
 func PromptForInput(prompt string, onDone func(value string) tea.Msg) tea.Msg {
 	return PromptForInputMsg{
 		Prompt: prompt,

internal/dynamo-browse/controllers/columns.go

@@ -0,0 +1,108 @@
+package controllers
+
+import (
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/lmika/audax/internal/common/ui/events"
+	"github.com/lmika/audax/internal/dynamo-browse/models"
+	"github.com/lmika/audax/internal/dynamo-browse/models/columns"
+	"github.com/lmika/audax/internal/dynamo-browse/models/queryexpr"
+	bus "github.com/lmika/events"
+)
+
+type ColumnsController struct {
+	// State
+	colModel  *columns.Columns
+	resultSet *models.ResultSet
+}
+
+func NewColumnsController(eventBus *bus.Bus) *ColumnsController {
+	cc := &ColumnsController{}
+
+	eventBus.On(newResultSetEvent, cc.onNewResultSet)
+	return cc
+}
+
+func (cc *ColumnsController) Columns() *columns.Columns {
+	return cc.colModel
+}
+
+func (cc *ColumnsController) ToggleVisible(idx int) tea.Msg {
+	cc.colModel.Columns[idx].Hidden = !cc.colModel.Columns[idx].Hidden
+	return ColumnsUpdated{}
+}
+
+func (cc *ColumnsController) ShiftColumnLeft(idx int) tea.Msg {
+	if idx == 0 {
+		return nil
+	}
+
+	col := cc.colModel.Columns[idx-1]
+	cc.colModel.Columns[idx-1], cc.colModel.Columns[idx] = cc.colModel.Columns[idx], col
+
+	return ColumnsUpdated{}
+}
+
+func (cc *ColumnsController) ShiftColumnRight(idx int) tea.Msg {
+	if idx >= len(cc.colModel.Columns)-1 {
+		return nil
+	}
+
+	col := cc.colModel.Columns[idx+1]
+	cc.colModel.Columns[idx+1], cc.colModel.Columns[idx] = cc.colModel.Columns[idx], col
+
+	return ColumnsUpdated{}
+}
+
+func (cc *ColumnsController) SetColumnsToResultSet() tea.Msg {
+	cc.colModel = columns.NewColumnsFromResultSet(cc.resultSet)
+	return ColumnsUpdated{}
+}
+
+func (cc *ColumnsController) onNewResultSet(rs *models.ResultSet, op resultSetUpdateOp) {
+	cc.resultSet = rs
+
+	if cc.colModel == nil || (op == resultSetUpdateInit || op == resultSetUpdateQuery) {
+		cc.colModel = columns.NewColumnsFromResultSet(rs)
+	}
+}
+
+func (cc *ColumnsController) AddColumn(afterIndex int) tea.Msg {
+	return events.PromptForInput("column expr: ", func(value string) tea.Msg {
+		colExpr, err := queryexpr.Parse(value)
+		if err != nil {
+			return events.Error(err)
+		}
+
+		newCol := columns.Column{
+			Name:      colExpr.String(),
+			Evaluator: columns.ExprFieldValueEvaluator{Expr: colExpr},
+		}
+
+		if afterIndex >= len(cc.colModel.Columns)-1 {
+			cc.colModel.Columns = append(cc.colModel.Columns, newCol)
+		} else {
+			newCols := make([]columns.Column, 0, len(cc.colModel.Columns)+1)
+
+			newCols = append(newCols, cc.colModel.Columns[:afterIndex+1]...)
+			newCols = append(newCols, newCol)
+			newCols = append(newCols, cc.colModel.Columns[afterIndex+1:]...)
+
+			cc.colModel.Columns = newCols
+		}
+
+		return ColumnsUpdated{}
+	})
+}
+
+func (cc *ColumnsController) DeleteColumn(afterIndex int) tea.Msg {
+	if len(cc.colModel.Columns) == 0 {
+		return nil
+	}
+
+	newCols := make([]columns.Column, 0, len(cc.colModel.Columns)-1)
+	newCols = append(newCols, cc.colModel.Columns[:afterIndex]...)
+	newCols = append(newCols, cc.colModel.Columns[afterIndex+1:]...)
+	cc.colModel.Columns = newCols
+
+	return ColumnsUpdated{}
+}

internal/dynamo-browse/controllers/ctrlevents.go

@@ -0,0 +1,5 @@
+package controllers
+
+const (
+	newResultSetEvent = "new_result_set"
+)

internal/dynamo-browse/controllers/events.go

@@ -13,6 +13,11 @@ type SetTableItemView struct {
 type SettingsUpdated struct {
 }
 
+type ColumnsUpdated struct {
+}
+
+type MoveLeftmostDisplayedColumnInTableViewBy int
+
 type NewResultSet struct {
 	ResultSet     *models.ResultSet
 	currentFilter string
@@ -59,3 +64,6 @@ type ResultSetUpdated struct {
 func (rs ResultSetUpdated) StatusMessage() string {
 	return rs.statusMessage
 }
+
+type ShowColumnOverlay struct{}
+type HideColumnOverlay struct{}

internal/dynamo-browse/controllers/export.go

@@ -0,0 +1,57 @@
+package controllers
+
+import (
+	"encoding/csv"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/lmika/audax/internal/common/ui/events"
+	"github.com/lmika/audax/internal/dynamo-browse/models"
+	"github.com/pkg/errors"
+	"os"
+)
+
+type ExportController struct {
+	state   *State
+	columns *ColumnsController
+}
+
+func NewExportController(state *State, columns *ColumnsController) *ExportController {
+	return &ExportController{state, columns}
+}
+
+func (c *ExportController) ExportCSV(filename string) tea.Msg {
+	resultSet := c.state.ResultSet()
+	if resultSet == nil {
+		return events.Error(errors.New("no result set"))
+	}
+
+	f, err := os.Create(filename)
+	if err != nil {
+		return events.Error(errors.Wrapf(err, "cannot export to '%v'", filename))
+	}
+	defer f.Close()
+
+	cw := csv.NewWriter(f)
+	defer cw.Flush()
+
+	columns := c.columns.Columns().VisibleColumns()
+
+	colNames := make([]string, len(columns))
+	for i, c := range columns {
+		colNames[i] = c.Name
+	}
+	if err := cw.Write(colNames); err != nil {
+		return events.Error(errors.Wrapf(err, "cannot export to '%v'", filename))
+	}
+
+	row := make([]string, len(columns))
+	for _, item := range resultSet.Items() {
+		for i, col := range columns {
+			row[i], _ = models.AttributeToString(col.Evaluator.EvaluateForItem(item))
+		}
+		if err := cw.Write(row); err != nil {
+			return events.Error(errors.Wrapf(err, "cannot export to '%v'", filename))
+		}
+	}
+
+	return nil
+}

internal/dynamo-browse/controllers/export_test.go

@@ -0,0 +1,88 @@
+package controllers_test
+
+import (
+	"github.com/stretchr/testify/assert"
+	"os"
+	"strings"
+	"testing"
+)
+
+func TestExportController_ExportCSV(t *testing.T) {
+	t.Run("should export result set to CSV file", func(t *testing.T) {
+		srv := newService(t, serviceConfig{tableName: "bravo-table"})
+
+		tempFile := tempFile(t)
+
+		invokeCommand(t, srv.readController.Init())
+		invokeCommand(t, srv.exportController.ExportCSV(tempFile))
+
+		bts, err := os.ReadFile(tempFile)
+		assert.NoError(t, err)
+
+		assert.Equal(t, string(bts), strings.Join([]string{
+			"pk,sk,alpha,beta,gamma\n",
+			"abc,222,This is another some value,1231,\n",
+			"bbb,131,,2468,foobar\n",
+			"foo,bar,This is some value,,\n",
+		}, ""))
+	})
+
+	t.Run("should return error if result set is not set", func(t *testing.T) {
+		srv := newService(t, serviceConfig{tableName: "non-existant-table"})
+
+		tempFile := tempFile(t)
+
+		invokeCommandExpectingError(t, srv.readController.Init())
+		invokeCommandExpectingError(t, srv.exportController.ExportCSV(tempFile))
+	})
+
+	t.Run("should honour new columns in CSV file", func(t *testing.T) {
+		srv := newService(t, serviceConfig{tableName: "alpha-table"})
+
+		tempFile := tempFile(t)
+
+		invokeCommand(t, srv.readController.Init())
+
+		invokeCommandWithPrompt(t, srv.columnsController.AddColumn(0), "address.no")
+		invokeCommand(t, srv.columnsController.ShiftColumnLeft(1))
+		invokeCommandWithPrompt(t, srv.columnsController.AddColumn(1), "address.street")
+		invokeCommand(t, srv.columnsController.ShiftColumnLeft(1))
+
+		invokeCommand(t, srv.exportController.ExportCSV(tempFile))
+
+		bts, err := os.ReadFile(tempFile)
+		assert.NoError(t, err)
+
+		assert.Equal(t, string(bts), strings.Join([]string{
+			"pk,address.no,address.street,sk,address,age,alpha,beta,gamma,useMailing\n",
+			"abc,123,Fake st.,111,,23,This is some value,,,true\n",
+			"abc,,,222,,,This is another some value,1231,,\n",
+			"bbb,,,131,,,,2468,foobar,\n",
+		}, ""))
+	})
+
+	t.Run("should honour hidden columns in CSV file", func(t *testing.T) {
+		srv := newService(t, serviceConfig{tableName: "alpha-table"})
+
+		tempFile := tempFile(t)
+
+		invokeCommand(t, srv.readController.Init())
+
+		invokeCommand(t, srv.columnsController.ToggleVisible(1))
+		invokeCommand(t, srv.columnsController.ToggleVisible(2))
+
+		invokeCommand(t, srv.exportController.ExportCSV(tempFile))
+
+		bts, err := os.ReadFile(tempFile)
+		assert.NoError(t, err)
+
+		assert.Equal(t, string(bts), strings.Join([]string{
+			"pk,age,alpha,beta,gamma,useMailing\n",
+			"abc,23,This is some value,,,true\n",
+			"abc,,This is another some value,1231,,\n",
+			"bbb,,,2468,foobar,\n",
+		}, ""))
+	})
+
+	// Hidden items?
+}

internal/dynamo-browse/controllers/tableread.go

@@ -2,7 +2,6 @@ package controllers
 
 import (
 	"context"
-	"encoding/csv"
 	"fmt"
 	tea "github.com/charmbracelet/bubbletea"
 	"github.com/lmika/audax/internal/common/ui/events"
@@ -11,18 +10,30 @@ import (
 	"github.com/lmika/audax/internal/dynamo-browse/models/serialisable"
 	"github.com/lmika/audax/internal/dynamo-browse/services/itemrenderer"
 	"github.com/lmika/audax/internal/dynamo-browse/services/workspaces"
+	bus "github.com/lmika/events"
 	"github.com/pkg/errors"
 	"golang.design/x/clipboard"
 	"log"
-	"os"
 	"strings"
 	"sync"
 )
 
+type resultSetUpdateOp int
+
+const (
+	resultSetUpdateInit resultSetUpdateOp = iota
+	resultSetUpdateQuery
+	resultSetUpdateFilter
+	resultSetUpdateSnapshotRestore
+	resultSetUpdateRescan
+	resultSetUpdateTouch
+)
+
 type TableReadController struct {
 	tableService        TableReadService
 	workspaceService    *workspaces.ViewSnapshotService
 	itemRendererService *itemrenderer.Service
+	eventBus            *bus.Bus
 	tableName           string
 	loadFromLastView    bool
 
@@ -37,14 +48,15 @@ func NewTableReadController(
 	tableService TableReadService,
 	workspaceService *workspaces.ViewSnapshotService,
 	itemRendererService *itemrenderer.Service,
+	eventBus *bus.Bus,
 	tableName string,
-	loadFromLastView bool,
 ) *TableReadController {
 	return &TableReadController{
 		state:               state,
 		tableService:        tableService,
 		workspaceService:    workspaceService,
 		itemRendererService: itemRendererService,
+		eventBus:            eventBus,
 		tableName:           tableName,
 		mutex:               new(sync.Mutex),
 	}
@@ -94,7 +106,7 @@ func (c *TableReadController) ScanTable(name string) tea.Msg {
 	}
 	resultSet = c.tableService.Filter(resultSet, c.state.Filter())
 
-	return c.setResultSetAndFilter(resultSet, c.state.Filter(), true)
+	return c.setResultSetAndFilter(resultSet, c.state.Filter(), true, resultSetUpdateInit)
 }
 
 func (c *TableReadController) PromptForQuery() tea.Msg {
@@ -117,7 +129,7 @@ func (c *TableReadController) runQuery(tableInfo *models.TableInfo, query, newFi
 			newResultSet = c.tableService.Filter(newResultSet, newFilter)
 		}
 
-		return c.setResultSetAndFilter(newResultSet, newFilter, pushSnapshot)
+		return c.setResultSetAndFilter(newResultSet, newFilter, pushSnapshot, resultSetUpdateQuery)
 	}
 
 	expr, err := queryexpr.Parse(query)
@@ -134,7 +146,7 @@ func (c *TableReadController) runQuery(tableInfo *models.TableInfo, query, newFi
 		if newFilter != "" {
 			newResultSet = c.tableService.Filter(newResultSet, newFilter)
 		}
-		return c.setResultSetAndFilter(newResultSet, newFilter, pushSnapshot)
+		return c.setResultSetAndFilter(newResultSet, newFilter, pushSnapshot, resultSetUpdateQuery)
 	})
 }
 
@@ -163,44 +175,11 @@ func (c *TableReadController) doIfNoneDirty(cmd tea.Cmd) tea.Msg {
 func (c *TableReadController) Rescan() tea.Msg {
 	return c.doIfNoneDirty(func() tea.Msg {
 		resultSet := c.state.ResultSet()
-		return c.doScan(context.Background(), resultSet, resultSet.Query, true)
+		return c.doScan(context.Background(), resultSet, resultSet.Query, true, resultSetUpdateRescan)
 	})
 }
 
-func (c *TableReadController) ExportCSV(filename string) tea.Msg {
+func (c *TableReadController) doScan(ctx context.Context, resultSet *models.ResultSet, query models.Queryable, pushBackstack bool, op resultSetUpdateOp) tea.Msg {
-	resultSet := c.state.ResultSet()
-	if resultSet == nil {
-		return events.Error(errors.New("no result set"))
-	}
-
-	f, err := os.Create(filename)
-	if err != nil {
-		return events.Error(errors.Wrapf(err, "cannot export to '%v'", filename))
-	}
-	defer f.Close()
-
-	cw := csv.NewWriter(f)
-	defer cw.Flush()
-
-	columns := resultSet.Columns()
-	if err := cw.Write(columns); err != nil {
-		return events.Error(errors.Wrapf(err, "cannot export to '%v'", filename))
-	}
-
-	row := make([]string, len(columns))
-	for _, item := range resultSet.Items() {
-		for i, col := range columns {
-			row[i], _ = item.AttributeValueAsString(col)
-		}
-		if err := cw.Write(row); err != nil {
-			return events.Error(errors.Wrapf(err, "cannot export to '%v'", filename))
-		}
-	}
-
-	return nil
-}
-
-func (c *TableReadController) doScan(ctx context.Context, resultSet *models.ResultSet, query models.Queryable, pushBackstack bool) tea.Msg {
 	newResultSet, err := c.tableService.ScanOrQuery(ctx, resultSet.TableInfo, query)
 	if err != nil {
 		return events.Error(err)
@@ -208,10 +187,10 @@ func (c *TableReadController) doScan(ctx context.Context, resultSet *models.Resu
 
 	newResultSet = c.tableService.Filter(newResultSet, c.state.Filter())
 
-	return c.setResultSetAndFilter(newResultSet, c.state.Filter(), pushBackstack)
+	return c.setResultSetAndFilter(newResultSet, c.state.Filter(), pushBackstack, op)
 }
 
-func (c *TableReadController) setResultSetAndFilter(resultSet *models.ResultSet, filter string, pushBackstack bool) tea.Msg {
+func (c *TableReadController) setResultSetAndFilter(resultSet *models.ResultSet, filter string, pushBackstack bool, op resultSetUpdateOp) tea.Msg {
 	if pushBackstack {
 		if err := c.workspaceService.PushSnapshot(resultSet, filter); err != nil {
 			log.Printf("cannot push snapshot: %v", err)
@@ -219,6 +198,9 @@ func (c *TableReadController) setResultSetAndFilter(resultSet *models.ResultSet,
 	}
 
 	c.state.setResultSetAndFilter(resultSet, filter)
+
+	c.eventBus.Fire(newResultSetEvent, resultSet, op)
+
 	return c.state.buildNewResultSetMessage("")
 }
 
@@ -238,7 +220,7 @@ func (c *TableReadController) Filter() tea.Msg {
 			resultSet := c.state.ResultSet()
 			newResultSet := c.tableService.Filter(resultSet, value)
 
-			return c.setResultSetAndFilter(newResultSet, value, true)
+			return c.setResultSetAndFilter(newResultSet, value, true, resultSetUpdateFilter)
 		},
 	}
 }
@@ -286,7 +268,7 @@ func (c *TableReadController) updateViewToSnapshot(viewSnapshot *serialisable.Vi
 		log.Printf("backstack: setting filter to '%v'", viewSnapshot.Filter)
 
 		newResultSet := c.tableService.Filter(currentResultSet, viewSnapshot.Filter)
-		return c.setResultSetAndFilter(newResultSet, viewSnapshot.Filter, false)
+		return c.setResultSetAndFilter(newResultSet, viewSnapshot.Filter, false, resultSetUpdateSnapshotRestore)
 	}
 
 	tableInfo := currentResultSet.TableInfo

internal/dynamo-browse/controllers/tableread_test.go

@@ -81,38 +81,6 @@ func TestTableReadController_Rescan(t *testing.T) {
 	})
 }
 
-func TestTableReadController_ExportCSV(t *testing.T) {
-	t.Run("should export result set to CSV file", func(t *testing.T) {
-		srv := newService(t, serviceConfig{tableName: "bravo-table"})
-
-		tempFile := tempFile(t)
-
-		invokeCommand(t, srv.readController.Init())
-		invokeCommand(t, srv.readController.ExportCSV(tempFile))
-
-		bts, err := os.ReadFile(tempFile)
-		assert.NoError(t, err)
-
-		assert.Equal(t, string(bts), strings.Join([]string{
-			"pk,sk,alpha,beta,gamma\n",
-			"abc,222,This is another some value,1231,\n",
-			"bbb,131,,2468,foobar\n",
-			"foo,bar,This is some value,,\n",
-		}, ""))
-	})
-
-	t.Run("should return error if result set is not set", func(t *testing.T) {
-		srv := newService(t, serviceConfig{tableName: "non-existant-table"})
-
-		tempFile := tempFile(t)
-
-		invokeCommandExpectingError(t, srv.readController.Init())
-		invokeCommandExpectingError(t, srv.readController.ExportCSV(tempFile))
-	})
-
-	// Hidden items?
-}
-
 func TestTableReadController_Query(t *testing.T) {
 	t.Run("should run scan with filter based on user query", func(t *testing.T) {
 		srv := newService(t, serviceConfig{tableName: "bravo-table"})
@@ -121,7 +89,7 @@ func TestTableReadController_Query(t *testing.T) {
 
 		invokeCommand(t, srv.readController.Init())
 		invokeCommandWithPrompts(t, srv.readController.PromptForQuery(), `pk ^= "abc"`)
-		invokeCommand(t, srv.readController.ExportCSV(tempFile))
+		invokeCommand(t, srv.exportController.ExportCSV(tempFile))
 
 		bts, err := os.ReadFile(tempFile)
 		assert.NoError(t, err)
@@ -138,7 +106,7 @@ func TestTableReadController_Query(t *testing.T) {
 		tempFile := tempFile(t)
 
 		invokeCommandExpectingError(t, srv.readController.Init())
-		invokeCommandExpectingError(t, srv.readController.ExportCSV(tempFile))
+		invokeCommandExpectingError(t, srv.exportController.ExportCSV(tempFile))
 	})
 }
 

internal/dynamo-browse/controllers/tablewrite.go

@@ -375,7 +375,7 @@ func (twc *TableWriteController) NoisyTouchItem(idx int) tea.Msg {
 				return events.Error(err)
 			}
 
-			return twc.tableReadControllers.doScan(ctx, resultSet, resultSet.Query, false)
+			return twc.tableReadControllers.doScan(ctx, resultSet, resultSet.Query, false, resultSetUpdateTouch)
 		},
 	}
 }
@@ -406,7 +406,7 @@ func (twc *TableWriteController) DeleteMarked() tea.Msg {
 				return events.Error(err)
 			}
 
-			return twc.tableReadControllers.doScan(ctx, resultSet, resultSet.Query, false)
+			return twc.tableReadControllers.doScan(ctx, resultSet, resultSet.Query, false, resultSetUpdateTouch)
 		},
 	}
 }

internal/dynamo-browse/controllers/tablewrite_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/lmika/audax/internal/dynamo-browse/services/tables"
 	workspaces_service "github.com/lmika/audax/internal/dynamo-browse/services/workspaces"
 	"github.com/lmika/audax/test/testdynamo"
+	bus "github.com/lmika/events"
 	"github.com/stretchr/testify/assert"
 	"testing"
 )
@@ -571,6 +572,8 @@ type services struct {
 	readController     *controllers.TableReadController
 	writeController    *controllers.TableWriteController
 	settingsController *controllers.SettingsController
+	columnsController  *controllers.ColumnsController
+	exportController   *controllers.ExportController
 }
 
 type serviceConfig struct {
@@ -590,11 +593,14 @@ func newService(t *testing.T, cfg serviceConfig) *services {
 
 	provider := dynamo.NewProvider(client)
 	service := tables.NewService(provider, settingStore)
+	eventBus := bus.New()
 
 	state := controllers.NewState()
-	readController := controllers.NewTableReadController(state, service, workspaceService, itemRendererService, cfg.tableName, false)
+	readController := controllers.NewTableReadController(state, service, workspaceService, itemRendererService, eventBus, cfg.tableName)
 	writeController := controllers.NewTableWriteController(state, service, readController, settingStore)
 	settingsController := controllers.NewSettingsController(settingStore)
+	columnsController := controllers.NewColumnsController(eventBus)
+	exportController := controllers.NewExportController(state, columnsController)
 
 	if cfg.isReadOnly {
 		if err := settingStore.SetReadOnly(cfg.isReadOnly); err != nil {
@@ -608,5 +614,7 @@ func newService(t *testing.T, cfg serviceConfig) *services {
 		readController:     readController,
 		writeController:    writeController,
 		settingsController: settingsController,
+		columnsController:  columnsController,
+		exportController:   exportController,
 	}
 }

internal/dynamo-browse/models/attrutils.go

@@ -34,7 +34,7 @@ func compareScalarAttributes(x, y types.AttributeValue) (int, bool) {
 	return 0, false
 }
 
-func attributeToString(x types.AttributeValue) (string, bool) {
+func AttributeToString(x types.AttributeValue) (string, bool) {
 	switch xVal := x.(type) {
 	case *types.AttributeValueMemberS:
 		return xVal.Value, true

internal/dynamo-browse/models/columns/columns.go

@@ -0,0 +1,69 @@
+package columns
+
+import (
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
+	"github.com/lmika/audax/internal/dynamo-browse/models"
+	"github.com/lmika/audax/internal/dynamo-browse/models/queryexpr"
+)
+
+type Columns struct {
+	TableInfo *models.TableInfo
+	Columns   []Column
+}
+
+func NewColumnsFromResultSet(rs *models.ResultSet) *Columns {
+	rsCols := rs.Columns()
+
+	cols := make([]Column, len(rsCols))
+	for i, c := range rsCols {
+		cols[i] = Column{
+			Name:      c,
+			Evaluator: SimpleFieldValueEvaluator(c),
+		}
+	}
+
+	return &Columns{
+		TableInfo: rs.TableInfo,
+		Columns:   cols,
+	}
+}
+
+func (cols *Columns) VisibleColumns() []Column {
+	if cols == nil {
+		return []Column{}
+	}
+
+	visibleCols := make([]Column, 0)
+	for _, col := range cols.Columns {
+		if col.Hidden {
+			continue
+		}
+		visibleCols = append(visibleCols, col)
+	}
+	return visibleCols
+}
+
+type Column struct {
+	Name      string
+	Evaluator FieldValueEvaluator
+	Hidden    bool
+}
+
+type FieldValueEvaluator interface {
+	EvaluateForItem(item models.Item) types.AttributeValue
+}
+
+type SimpleFieldValueEvaluator string
+
+func (sfve SimpleFieldValueEvaluator) EvaluateForItem(item models.Item) types.AttributeValue {
+	return item[string(sfve)]
+}
+
+type ExprFieldValueEvaluator struct {
+	Expr *queryexpr.QueryExpr
+}
+
+func (sfve ExprFieldValueEvaluator) EvaluateForItem(item models.Item) types.AttributeValue {
+	val, _ := sfve.Expr.EvalItem(item)
+	return val
+}

internal/dynamo-browse/models/items.go

@@ -2,7 +2,6 @@ package models
 
 import (
 	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
-	"github.com/lmika/audax/internal/dynamo-browse/models/itemrender"
 )
 
 type ItemIndex struct {
@@ -34,9 +33,5 @@ func (i Item) KeyValue(info *TableInfo) map[string]types.AttributeValue {
 }
 
 func (i Item) AttributeValueAsString(key string) (string, bool) {
-	return attributeToString(i[key])
+	return AttributeToString(i[key])
-}
-
-func (i Item) Renderer(key string) itemrender.Renderer {
-	return itemrender.ToRenderer(i[key])
 }

internal/dynamo-browse/models/queryexpr/ast.go

@@ -2,6 +2,7 @@ package queryexpr
 
 import (
 	"github.com/alecthomas/participle/v2"
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
 	"github.com/lmika/audax/internal/dynamo-browse/models"
 	"github.com/pkg/errors"
 )
@@ -17,6 +18,10 @@ func (a *astExpr) evalToIR(tableInfo *models.TableInfo) (*irDisjunction, error)
 	return a.Root.evalToIR(tableInfo)
 }
 
+func (a *astExpr) evalItem(item models.Item) (types.AttributeValue, error) {
+	return a.Root.evalItem(item)
+}
+
 type astDisjunction struct {
 	Operands []*astConjunction `parser:"@@ ('or' @@)*"`
 }
@@ -25,10 +30,16 @@ type astConjunction struct {
 	Operands []*astBinOp `parser:"@@ ('and' @@)*"`
 }
 
+// TODO: do this properly
 type astBinOp struct {
+	Ref   *astDot          `parser:"@@"`
+	Op    string           `parser:"( @('^' '=' | '=')"`
+	Value *astLiteralValue `parser:"@@ )?"`
+}
+
+type astDot struct {
 	Name  string   `parser:"@Ident"`
-	Op    string           `parser:"@('^' '=' | '=')"`
+	Quals []string `parser:"('.' @Ident)*"`
-	Value *astLiteralValue `parser:"@@"`
 }
 
 type astLiteralValue struct {

internal/dynamo-browse/models/queryexpr/binops.go

@@ -2,6 +2,7 @@ package queryexpr
 
 import (
 	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/expression"
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
 	"github.com/lmika/audax/internal/dynamo-browse/models"
 	"github.com/pkg/errors"
 )
@@ -12,22 +13,40 @@ func (a *astBinOp) evalToIR(info *models.TableInfo) (irAtom, error) {
 		return nil, err
 	}
 
+	singleName, isSingleName := a.Ref.unqualifiedName()
+	if !isSingleName {
+		return nil, errors.Errorf("%v: cannot use dereferences", singleName)
+	}
+
 	switch a.Op {
 	case "=":
-		return irFieldEq{name: a.Name, value: v}, nil
+		return irFieldEq{name: singleName, value: v}, nil
 	case "^=":
 		strValue, isStrValue := v.(string)
 		if !isStrValue {
 			return nil, errors.New("operand '^=' must be string")
 		}
-		return irFieldBeginsWith{name: a.Name, prefix: strValue}, nil
+		return irFieldBeginsWith{name: singleName, prefix: strValue}, nil
 	}
 
 	return nil, errors.Errorf("unrecognised operator: %v", a.Op)
 }
 
+func (a *astBinOp) evalItem(item models.Item) (types.AttributeValue, error) {
+	left, err := a.Ref.evalItem(item)
+	if err != nil {
+		return nil, err
+	}
+
+	if a.Op == "" {
+		return left, nil
+	}
+
+	return nil, errors.New("TODO")
+}
+
 func (a *astBinOp) String() string {
-	return a.Name + a.Op + a.Value.String()
+	return a.Ref.String() + a.Op + a.Value.String()
 }
 
 type irFieldEq struct {

internal/dynamo-browse/models/queryexpr/conj.go

@@ -2,6 +2,7 @@ package queryexpr
 
 import (
 	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/expression"
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
 	"github.com/lmika/audax/internal/dynamo-browse/models"
 	"github.com/pkg/errors"
 	"strings"
@@ -20,6 +21,14 @@ func (a *astConjunction) evalToIR(tableInfo *models.TableInfo) (*irConjunction,
 	return &irConjunction{atoms: atoms}, nil
 }
 
+func (a *astConjunction) evalItem(item models.Item) (types.AttributeValue, error) {
+	if len(a.Operands) == 1 {
+		return a.Operands[0].evalItem(item)
+	}
+
+	return nil, errors.New("TODO")
+}
+
 func (d *astConjunction) String() string {
 	sb := new(strings.Builder)
 	for i, operand := range d.Operands {

internal/dynamo-browse/models/queryexpr/disj.go

@@ -2,6 +2,7 @@ package queryexpr
 
 import (
 	"github.com/aws/aws-sdk-go-v2/feature/dynamodb/expression"
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
 	"github.com/lmika/audax/internal/dynamo-browse/models"
 	"github.com/pkg/errors"
 	"strings"
@@ -20,6 +21,14 @@ func (a *astDisjunction) evalToIR(tableInfo *models.TableInfo) (*irDisjunction,
 	return &irDisjunction{conj: conj}, nil
 }
 
+func (a *astDisjunction) evalItem(item models.Item) (types.AttributeValue, error) {
+	if len(a.Operands) == 1 {
+		return a.Operands[0].evalItem(item)
+	}
+
+	return nil, errors.New("TODO")
+}
+
 func (d *astDisjunction) String() string {
 	sb := new(strings.Builder)
 	for i, operand := range d.Operands {

internal/dynamo-browse/models/queryexpr/dot.go

@@ -0,0 +1,47 @@
+package queryexpr
+
+import (
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
+	"github.com/lmika/audax/internal/dynamo-browse/models"
+	"strings"
+)
+
+func (dt *astDot) unqualifiedName() (string, bool) {
+	if len(dt.Quals) == 0 {
+		return dt.Name, true
+	}
+	return "", false
+}
+
+func (dt *astDot) evalItem(item models.Item) (types.AttributeValue, error) {
+	res, hasV := item[dt.Name]
+	if !hasV {
+		return nil, NameNotFoundError(dt.String())
+	}
+
+	for i, qualName := range dt.Quals {
+		mapRes, isMapRes := res.(*types.AttributeValueMemberM)
+		if !isMapRes {
+			return nil, ValueNotAMapError(append([]string{dt.Name}, dt.Quals[:i+1]...))
+		}
+
+		res, hasV = mapRes.Value[qualName]
+		if !hasV {
+			return nil, NameNotFoundError(dt.String())
+		}
+	}
+
+	return res, nil
+}
+
+func (a *astDot) String() string {
+	var sb strings.Builder
+
+	sb.WriteString(a.Name)
+	for _, q := range a.Quals {
+		sb.WriteRune('.')
+		sb.WriteString(q)
+	}
+
+	return sb.String()
+}

internal/dynamo-browse/models/queryexpr/errors.go

@@ -0,0 +1,20 @@
+package queryexpr
+
+import (
+	"fmt"
+	"strings"
+)
+
+// NameNotFoundError is returned if the given name cannot be found
+type NameNotFoundError string
+
+func (n NameNotFoundError) Error() string {
+	return fmt.Sprintf("%v: name not found", string(n))
+}
+
+// ValueNotAMapError is return if the given name is not a map
+type ValueNotAMapError []string
+
+func (n ValueNotAMapError) Error() string {
+	return fmt.Sprintf("%v: name is not a map", strings.Join(n, "."))
+}

internal/dynamo-browse/models/queryexpr/expr.go

@@ -1,6 +1,9 @@
 package queryexpr
 
-import "github.com/lmika/audax/internal/dynamo-browse/models"
+import (
+	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
+	"github.com/lmika/audax/internal/dynamo-browse/models"
+)
 
 type QueryExpr struct {
 	ast *astExpr
@@ -15,6 +18,10 @@ func (md *QueryExpr) Plan(tableInfo *models.TableInfo) (*models.QueryExecutionPl
 	return ir.calcQuery(tableInfo)
 }
 
+func (md *QueryExpr) EvalItem(item models.Item) (types.AttributeValue, error) {
+	return md.ast.evalItem(item)
+}
+
 func (md *QueryExpr) String() string {
 	return md.ast.String()
 }

internal/dynamo-browse/models/queryexpr/expr_test.go

@@ -132,3 +132,67 @@ func TestModExpr_Query(t *testing.T) {
 		})
 	})
 }
+
+func TestQueryExpr_EvalItem(t *testing.T) {
+	var (
+		item = models.Item{
+			"alpha": &types.AttributeValueMemberS{Value: "alpha"},
+			"bravo": &types.AttributeValueMemberN{Value: "123"},
+			"charlie": &types.AttributeValueMemberM{
+				Value: map[string]types.AttributeValue{
+					"door": &types.AttributeValueMemberS{Value: "red"},
+					"tree": &types.AttributeValueMemberS{Value: "green"},
+				},
+			},
+		}
+	)
+
+	t.Run("simple values", func(t *testing.T) {
+		scenarios := []struct {
+			expr     string
+			expected types.AttributeValue
+		}{
+			// Simple values
+			{expr: `alpha`, expected: &types.AttributeValueMemberS{Value: "alpha"}},
+			{expr: `bravo`, expected: &types.AttributeValueMemberN{Value: "123"}},
+			{expr: `charlie`, expected: item["charlie"]},
+
+			// Dot values
+			{expr: `charlie.door`, expected: &types.AttributeValueMemberS{Value: "red"}},
+			{expr: `charlie.tree`, expected: &types.AttributeValueMemberS{Value: "green"}},
+		}
+		for _, scenario := range scenarios {
+			t.Run(scenario.expr, func(t *testing.T) {
+				modExpr, err := queryexpr.Parse(scenario.expr)
+				assert.NoError(t, err)
+
+				res, err := modExpr.EvalItem(item)
+				assert.NoError(t, err)
+
+				assert.Equal(t, scenario.expected, res)
+			})
+		}
+	})
+
+	t.Run("expression errors", func(t *testing.T) {
+		scenarios := []struct {
+			expr          string
+			expectedError error
+		}{
+			{expr: `not_present`, expectedError: queryexpr.NameNotFoundError("not_present")},
+			{expr: `alpha.bravo`, expectedError: queryexpr.ValueNotAMapError([]string{"alpha", "bravo"})},
+			{expr: `charlie.tree.bla`, expectedError: queryexpr.ValueNotAMapError([]string{"charlie", "tree", "bla"})},
+		}
+
+		for _, scenario := range scenarios {
+			t.Run(scenario.expr, func(t *testing.T) {
+				modExpr, err := queryexpr.Parse(scenario.expr)
+				assert.NoError(t, err)
+
+				res, err := modExpr.EvalItem(item)
+				assert.Nil(t, res)
+				assert.Equal(t, scenario.expectedError, err)
+			})
+		}
+	})
+}

internal/dynamo-browse/models/queryexpr/values.go

@@ -8,6 +8,10 @@ import (
 )
 
 func (a *astLiteralValue) dynamoValue() (types.AttributeValue, error) {
+	if a == nil {
+		return nil, nil
+	}
+
 	s, err := strconv.Unquote(a.StringVal)
 	if err != nil {
 		return nil, errors.Wrap(err, "cannot unquote string")
@@ -16,6 +20,10 @@ func (a *astLiteralValue) dynamoValue() (types.AttributeValue, error) {
 }
 
 func (a *astLiteralValue) goValue() (any, error) {
+	if a == nil {
+		return nil, nil
+	}
+
 	s, err := strconv.Unquote(a.StringVal)
 	if err != nil {
 		return nil, errors.Wrap(err, "cannot unquote string")
@@ -24,5 +32,8 @@ func (a *astLiteralValue) goValue() (any, error) {
 }
 
 func (a *astLiteralValue) String() string {
+	if a == nil {
+		return ""
+	}
 	return a.StringVal
 }

internal/dynamo-browse/models/tableinfo.go

@@ -6,6 +6,13 @@ type TableInfo struct {
 	DefinedAttributes []string
 }
 
+func (ti *TableInfo) Equal(other *TableInfo) bool {
+	return ti.Name == other.Name &&
+		ti.Keys.PartitionKey == other.Keys.PartitionKey &&
+		ti.Keys.SortKey == other.Keys.SortKey &&
+		len(ti.DefinedAttributes) == len(other.DefinedAttributes) // Probably should be all
+}
+
 type KeyAttribute struct {
 	PartitionKey string
 	SortKey      string

internal/dynamo-browse/services/itemrenderer/service.go

@@ -32,13 +32,13 @@ func (s *Service) RenderItem(w io.Writer, item models.Item, resultSet *models.Re
 	seenColumns := make(map[string]struct{})
 	for _, colName := range resultSet.Columns() {
 		seenColumns[colName] = struct{}{}
-		if r := item.Renderer(colName); r != nil {
+		if r := itemrender.ToRenderer(item[colName]); r != nil {
 			s.renderItem(tabWriter, "", colName, r, styles)
 		}
 	}
 	for k, _ := range item {
 		if _, seen := seenColumns[k]; !seen {
-			if r := item.Renderer(k); r != nil {
+			if r := itemrender.ToRenderer(item[k]); r != nil {
 				s.renderItem(tabWriter, "", k, r, styles)
 			}
 		}

internal/dynamo-browse/ui/keybindings/defaults.go

@@ -4,6 +4,15 @@ import "github.com/charmbracelet/bubbles/key"
 
 func Default() *KeyBindings {
 	return &KeyBindings{
+		ColumnPopup: &FieldsPopupBinding{
+			Close:            key.NewBinding(key.WithKeys("ctrl+c", "esc"), key.WithHelp("ctrl+c/esc", "close popup")),
+			ShiftColumnLeft:  key.NewBinding(key.WithKeys("I", "shift column left")),
+			ShiftColumnRight: key.NewBinding(key.WithKeys("K", "shift column right")),
+			ToggleVisible:    key.NewBinding(key.WithKeys(" ", "toggle column visible")),
+			ResetColumns:     key.NewBinding(key.WithKeys("R", "reset columns")),
+			AddColumn:        key.NewBinding(key.WithKeys("a", "add new column")),
+			DeleteColumn:     key.NewBinding(key.WithKeys("d", "delete column")),
+		},
 		TableView: &TableKeyBinding{
 			MoveUp:   key.NewBinding(key.WithKeys("i", "up")),
 			MoveDown: key.NewBinding(key.WithKeys("k", "down")),
@@ -25,6 +34,7 @@ func Default() *KeyBindings {
 			CycleLayoutForward:   key.NewBinding(key.WithKeys("w"), key.WithHelp("w", "cycle layout forward")),
 			CycleLayoutBackwards: key.NewBinding(key.WithKeys("W"), key.WithHelp("W", "cycle layout backward")),
 			PromptForCommand:     key.NewBinding(key.WithKeys(":"), key.WithHelp(":", "prompt for command")),
+			ShowColumnOverlay:    key.NewBinding(key.WithKeys("f"), key.WithHelp("f", "show column overlay")),
 			Quit:                 key.NewBinding(key.WithKeys("ctrl+c", "esc"), key.WithHelp("ctrl+c/esc", "quit")),
 		},
 	}

internal/dynamo-browse/ui/keybindings/keybindings.go

@@ -3,10 +3,21 @@ package keybindings
 import "github.com/charmbracelet/bubbles/key"
 
 type KeyBindings struct {
+	ColumnPopup *FieldsPopupBinding `keymap:"column-popup"`
 	TableView   *TableKeyBinding    `keymap:"item-table"`
 	View        *ViewKeyBindings    `keymap:"view"`
 }
 
+type FieldsPopupBinding struct {
+	Close            key.Binding `keymap:"close"`
+	ShiftColumnLeft  key.Binding `keymap:"shift-column-left"`
+	ShiftColumnRight key.Binding `keymap:"shift-column-right"`
+	ToggleVisible    key.Binding `keymap:"toggle-column-visible"`
+	ResetColumns     key.Binding `keymap:"reset-columns"`
+	AddColumn        key.Binding `keymap:"add-column"`
+	DeleteColumn     key.Binding `keymap:"delete-column"`
+}
+
 type TableKeyBinding struct {
 	MoveUp   key.Binding `keymap:"move-up"`
 	MoveDown key.Binding `keymap:"move-down"`
@@ -30,5 +41,6 @@ type ViewKeyBindings struct {
 	CycleLayoutForward   key.Binding `keymap:"cycle-layout-forward"`
 	CycleLayoutBackwards key.Binding `keymap:"cycle-layout-backwards"`
 	PromptForCommand     key.Binding `keymap:"prompt-for-command"`
+	ShowColumnOverlay    key.Binding `keymap:"show-column-overlay"`
 	Quit                 key.Binding `keymap:"quit"`
 }

internal/dynamo-browse/ui/model.go

@@ -9,6 +9,7 @@ import (
 	"github.com/lmika/audax/internal/dynamo-browse/models"
 	"github.com/lmika/audax/internal/dynamo-browse/services/itemrenderer"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/keybindings"
+	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/colselector"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/dialogprompt"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/dynamoitemedit"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/dynamoitemview"
@@ -40,7 +41,9 @@ type Model struct {
 	tableReadController  *controllers.TableReadController
 	tableWriteController *controllers.TableWriteController
 	settingsController   *controllers.SettingsController
+	exportController     *controllers.ExportController
 	commandController    *commandctrl.CommandController
+	colSelector          *colselector.Model
 	itemEdit             *dynamoitemedit.Model
 	statusAndPrompt      *statusandprompt.StatusAndPrompt
 	tableSelect          *tableselect.Model
@@ -57,6 +60,8 @@ type Model struct {
 func NewModel(
 	rc *controllers.TableReadController,
 	wc *controllers.TableWriteController,
+	columnsController *controllers.ColumnsController,
+	exportController *controllers.ExportController,
 	settingsController *controllers.SettingsController,
 	itemRendererService *itemrenderer.Service,
 	cc *commandctrl.CommandController,
@@ -65,11 +70,12 @@ func NewModel(
 ) Model {
 	uiStyles := styles.DefaultStyles
 
-	dtv := dynamotableview.New(defaultKeyMap.TableView, settingsController, uiStyles)
+	dtv := dynamotableview.New(defaultKeyMap.TableView, columnsController, settingsController, uiStyles)
 	div := dynamoitemview.New(itemRendererService, uiStyles)
 	mainView := layout.NewVBox(layout.LastChildFixedAt(14), dtv, div)
 
-	itemEdit := dynamoitemedit.NewModel(mainView)
+	colSelector := colselector.New(mainView, defaultKeyMap, columnsController)
+	itemEdit := dynamoitemedit.NewModel(colSelector)
 	statusAndPrompt := statusandprompt.New(itemEdit, "", uiStyles.StatusAndPrompt)
 	dialogPrompt := dialogprompt.New(statusAndPrompt)
 	tableSelect := tableselect.New(dialogPrompt, uiStyles)
@@ -88,7 +94,7 @@ func NewModel(
 				if len(args) == 0 {
 					return events.Error(errors.New("expected filename"))
 				}
-				return rc.ExportCSV(args[0])
+				return exportController.ExportCSV(args[0])
 			},
 			"unmark": commandctrl.NoArgCommand(rc.Unmark),
 			"delete": commandctrl.NoArgCommand(wc.DeleteMarked),
@@ -174,6 +180,7 @@ func NewModel(
 		tableWriteController: wc,
 		commandController:    cc,
 		itemEdit:             itemEdit,
+		colSelector:          colSelector,
 		statusAndPrompt:      statusAndPrompt,
 		tableSelect:          tableSelect,
 		root:                 root,
@@ -184,16 +191,6 @@ func NewModel(
 	}
 }
 
-func (m Model) Init() tea.Cmd {
-	// TODO: this should probably be moved somewhere else
-	rcFilename := os.ExpandEnv(initRCFilename)
-	if err := m.commandController.ExecuteFile(rcFilename); err != nil {
-		log.Println(err)
-	}
-
-	return m.tableReadController.Init
-}
-
 func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	switch msg := msg.(type) {
 	case controllers.SetTableItemView:
@@ -205,15 +202,16 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			events.SetStatus(msg.StatusMessage()),
 		)
 	case tea.KeyMsg:
-		if !m.statusAndPrompt.InPrompt() && !m.tableSelect.Visible() {
+		// TODO: use modes here
+		if !m.statusAndPrompt.InPrompt() && !m.tableSelect.Visible() && !m.colSelector.ColSelectorVisible() {
 			switch {
 			case key.Matches(msg, m.keyMap.Mark):
 				if idx := m.tableView.SelectedItemIndex(); idx >= 0 {
-					return m, func() tea.Msg { return m.tableWriteController.ToggleMark(idx) }
+					return m, events.SetTeaMessage(m.tableWriteController.ToggleMark(idx))
 				}
 			case key.Matches(msg, m.keyMap.CopyItemToClipboard):
 				if idx := m.tableView.SelectedItemIndex(); idx >= 0 {
-					return m, func() tea.Msg { return m.tableReadController.CopyItemToClipboard(idx) }
+					return m, events.SetTeaMessage(m.tableReadController.CopyItemToClipboard(idx))
 				}
 			case key.Matches(msg, m.keyMap.Rescan):
 				return m, m.tableReadController.Rescan
@@ -226,22 +224,18 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			case key.Matches(msg, m.keyMap.ViewForward):
 				return m, m.tableReadController.ViewForward
 			case key.Matches(msg, m.keyMap.CycleLayoutForward):
-				return m, func() tea.Msg {
+				return m, events.SetTeaMessage(controllers.SetTableItemView{ViewIndex: utils.Cycle(m.mainViewIndex, 1, ViewModeCount)})
-					return controllers.SetTableItemView{ViewIndex: utils.Cycle(m.mainViewIndex, 1, ViewModeCount)}
-				}
 			case key.Matches(msg, m.keyMap.CycleLayoutBackwards):
-				return m, func() tea.Msg {
+				return m, events.SetTeaMessage(controllers.SetTableItemView{ViewIndex: utils.Cycle(m.mainViewIndex, -1, ViewModeCount)})
-					return controllers.SetTableItemView{ViewIndex: utils.Cycle(m.mainViewIndex, -1, ViewModeCount)}
-				}
 			//case "e":
 			//	m.itemEdit.Visible()
 			//	return m, nil
+			case key.Matches(msg, m.keyMap.ShowColumnOverlay):
+				return m, events.SetTeaMessage(controllers.ShowColumnOverlay{})
 			case key.Matches(msg, m.keyMap.PromptForCommand):
 				return m, m.commandController.Prompt
 			case key.Matches(msg, m.keyMap.PromptForTable):
-				return m, func() tea.Msg {
+				return m, events.SetTeaMessage(m.tableReadController.ListTables())
-					return m.tableReadController.ListTables()
-				}
 			case key.Matches(msg, m.keyMap.Quit):
 				return m, tea.Quit
 			}
@@ -253,6 +247,16 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	return m, cmd
 }
 
+func (m Model) Init() tea.Cmd {
+	// TODO: this should probably be moved somewhere else
+	rcFilename := os.ExpandEnv(initRCFilename)
+	if err := m.commandController.ExecuteFile(rcFilename); err != nil {
+		log.Println(err)
+	}
+
+	return m.tableReadController.Init
+}
+
 func (m Model) View() string {
 	return m.root.View()
 }

internal/dynamo-browse/ui/teamodels/colselector/colmodel.go

@@ -0,0 +1,158 @@
+package colselector
+
+import (
+	"github.com/charmbracelet/bubbles/key"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+	"github.com/lmika/audax/internal/common/ui/events"
+	"github.com/lmika/audax/internal/dynamo-browse/controllers"
+	"github.com/lmika/audax/internal/dynamo-browse/models/columns"
+	"github.com/lmika/audax/internal/dynamo-browse/ui/keybindings"
+	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/layout"
+	table "github.com/lmika/go-bubble-table"
+	"strings"
+)
+
+var frameColor = lipgloss.Color("63")
+
+var frameStyle = lipgloss.NewStyle().
+	Foreground(frameColor)
+var style = lipgloss.NewStyle().
+	BorderStyle(lipgloss.NormalBorder()).
+	BorderForeground(frameColor)
+
+type colListModel struct {
+	keyBinding    *keybindings.KeyBindings
+	colController *controllers.ColumnsController
+
+	rows  []table.Row
+	table table.Model
+}
+
+func newColListModel(keyBinding *keybindings.KeyBindings, colController *controllers.ColumnsController) *colListModel {
+	tbl := table.New(table.SimpleColumns([]string{"", "Name"}), 100, 100)
+	tbl.SetRows([]table.Row{})
+
+	return &colListModel{
+		keyBinding:    keyBinding,
+		colController: colController,
+		table:         tbl,
+	}
+}
+
+func (c *colListModel) Init() tea.Cmd {
+	return nil
+}
+
+func (m *colListModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case tea.KeyMsg:
+		switch {
+		// Column operations
+		case key.Matches(msg, m.keyBinding.ColumnPopup.ShiftColumnLeft):
+			return m, events.SetTeaMessage(m.shiftColumnUp(m.table.Cursor()))
+		case key.Matches(msg, m.keyBinding.ColumnPopup.ShiftColumnRight):
+			return m, events.SetTeaMessage(m.shiftColumnDown(m.table.Cursor()))
+		case key.Matches(msg, m.keyBinding.ColumnPopup.ToggleVisible):
+			return m, events.SetTeaMessage(m.colController.ToggleVisible(m.table.Cursor()))
+		case key.Matches(msg, m.keyBinding.ColumnPopup.Close):
+			return m, events.SetTeaMessage(controllers.HideColumnOverlay{})
+		case key.Matches(msg, m.keyBinding.ColumnPopup.ResetColumns):
+			return m, events.SetTeaMessage(m.colController.SetColumnsToResultSet())
+		case key.Matches(msg, m.keyBinding.ColumnPopup.AddColumn):
+			return m, events.SetTeaMessage(m.colController.AddColumn(m.table.Cursor()))
+		case key.Matches(msg, m.keyBinding.ColumnPopup.DeleteColumn):
+			return m, events.SetTeaMessage(m.colController.DeleteColumn(m.table.Cursor()))
+
+		// Main table nav
+		case key.Matches(msg, m.keyBinding.TableView.ColLeft):
+			return m, events.SetTeaMessage(controllers.MoveLeftmostDisplayedColumnInTableViewBy(-1))
+		case key.Matches(msg, m.keyBinding.TableView.ColRight):
+			return m, events.SetTeaMessage(controllers.MoveLeftmostDisplayedColumnInTableViewBy(1))
+
+		// Table nav
+		case key.Matches(msg, m.keyBinding.TableView.MoveUp):
+			m.table.GoUp()
+			return m, nil
+		case key.Matches(msg, m.keyBinding.TableView.MoveDown):
+			m.table.GoDown()
+			return m, nil
+		case key.Matches(msg, m.keyBinding.TableView.PageUp):
+			m.table.GoPageUp()
+			return m, nil
+		case key.Matches(msg, m.keyBinding.TableView.PageDown):
+			m.table.GoPageDown()
+			return m, nil
+		case key.Matches(msg, m.keyBinding.TableView.Home):
+			m.table.GoTop()
+			return m, nil
+		case key.Matches(msg, m.keyBinding.TableView.End):
+			m.table.GoBottom()
+			return m, nil
+		}
+	}
+
+	var cmd tea.Cmd
+	m.table, cmd = m.table.Update(msg)
+	return m, cmd
+}
+
+func (c *colListModel) View() string {
+	innerView := lipgloss.JoinVertical(
+		lipgloss.Top,
+		lipgloss.PlaceHorizontal(overlayWidth-2, lipgloss.Center, "Columns"),
+		frameStyle.Render(strings.Repeat(lipgloss.NormalBorder().Top, 48)),
+		c.table.View(),
+	)
+
+	view := style.Width(overlayWidth - 2).Height(overlayHeight - 2).Render(innerView)
+
+	return view
+}
+
+func (c *colListModel) Resize(w, h int) layout.ResizingModel {
+	c.table.SetSize(overlayWidth-4, overlayHeight-4)
+	return c
+}
+
+func (c *colListModel) refreshTable() {
+	colsFromController := c.colController.Columns()
+	if len(c.rows) != len(colsFromController.Columns) {
+		c.setColumnsFromModel(colsFromController)
+	}
+	c.table.UpdateView()
+}
+
+func (c *colListModel) setColumnsFromModel(cols *columns.Columns) {
+	if cols == nil {
+		c.table.SetRows([]table.Row{})
+		return
+	}
+
+	colNames := make([]table.Row, len(cols.Columns))
+	for i := range cols.Columns {
+		colNames[i] = colListRowModel{c}
+	}
+	c.rows = colNames
+	c.table.SetRows(colNames)
+
+	if c.table.Cursor() >= len(c.rows) {
+		c.table.GoBottom()
+	}
+}
+
+func (c *colListModel) shiftColumnUp(cursor int) tea.Msg {
+	msg := c.colController.ShiftColumnLeft(cursor)
+	if msg != nil {
+		c.table.GoUp()
+	}
+	return msg
+}
+
+func (c *colListModel) shiftColumnDown(cursor int) tea.Msg {
+	msg := c.colController.ShiftColumnRight(cursor)
+	if msg != nil {
+		c.table.GoDown()
+	}
+	return msg
+}

internal/dynamo-browse/ui/teamodels/colselector/model.go

@@ -0,0 +1,74 @@
+package colselector
+
+import (
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/lmika/audax/internal/dynamo-browse/controllers"
+	"github.com/lmika/audax/internal/dynamo-browse/ui/keybindings"
+	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/layout"
+	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/utils"
+)
+
+const (
+	overlayWidth  = 50
+	overlayHeight = 25
+)
+
+type Model struct {
+	columnsController *controllers.ColumnsController
+	subModel          tea.Model
+	colListModel      *colListModel
+	compositor        *layout.Compositor
+	w, h              int
+}
+
+func New(submodel tea.Model, keyBinding *keybindings.KeyBindings, columnsController *controllers.ColumnsController) *Model {
+	colListModel := newColListModel(keyBinding, columnsController)
+
+	compositor := layout.NewCompositor(submodel)
+
+	return &Model{
+		columnsController: columnsController,
+		subModel:          submodel,
+		compositor:        compositor,
+		colListModel:      colListModel,
+	}
+}
+
+func (m *Model) Init() tea.Cmd {
+	return m.subModel.Init()
+}
+
+func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	var cc utils.CmdCollector
+	switch msg := msg.(type) {
+	case controllers.ShowColumnOverlay:
+		m.colListModel.setColumnsFromModel(m.columnsController.Columns())
+		m.compositor.SetOverlay(m.colListModel, m.w/2-overlayWidth/2, m.h/2-overlayHeight/2, overlayWidth, overlayHeight)
+	case controllers.HideColumnOverlay:
+		m.compositor.ClearOverlay()
+	case controllers.ColumnsUpdated:
+		m.colListModel.refreshTable()
+		m.subModel = cc.Collect(m.subModel.Update(msg))
+	case tea.KeyMsg:
+		m.compositor = cc.Collect(m.compositor.Update(msg)).(*layout.Compositor)
+	default:
+		m.subModel = cc.Collect(m.subModel.Update(msg))
+	}
+	return m, cc.Cmd()
+}
+
+func (m *Model) View() string {
+	return m.compositor.View()
+}
+
+func (m *Model) Resize(w, h int) layout.ResizingModel {
+	m.w, m.h = w, h
+	m.compositor.MoveOverlay(m.w/2-overlayWidth/2, m.h/2-overlayHeight/2)
+	m.subModel = layout.Resize(m.subModel, w, h)
+	m.colListModel = layout.Resize(m.colListModel, w, h).(*colListModel)
+	return m
+}
+
+func (m *Model) ColSelectorVisible() bool {
+	return m.compositor.HasOverlay()
+}

internal/dynamo-browse/ui/teamodels/colselector/tblmodel.go

@@ -0,0 +1,31 @@
+package colselector
+
+import (
+	"fmt"
+	"github.com/charmbracelet/lipgloss"
+	table "github.com/lmika/go-bubble-table"
+	"io"
+)
+
+type colListRowModel struct {
+	m *colListModel
+}
+
+func (clr colListRowModel) Render(w io.Writer, model table.Model, index int) {
+	cols := clr.m.colController.Columns()
+	if cols == nil {
+		return
+	}
+
+	var style lipgloss.Style
+	if index == model.Cursor() {
+		style = model.Styles.SelectedRow
+	}
+
+	col := clr.m.colController.Columns().Columns[index]
+	if !col.Hidden {
+		fmt.Fprintln(w, style.Render(fmt.Sprintf(".\t%v", col.Name)))
+	} else {
+		fmt.Fprintln(w, style.Render(fmt.Sprintf("✕\t%v", col.Name)))
+	}
+}

internal/dynamo-browse/ui/teamodels/dynamotableview/colmodel.go

@@ -5,7 +5,7 @@ type columnModel struct {
 }
 
 func (cm columnModel) Len() int {
-	return len(cm.m.resultSet.Columns()[cm.m.colOffset:]) + 1
+	return len(cm.m.columns[cm.m.colOffset:]) + 1
 }
 
 func (cm columnModel) Header(index int) string {
@@ -13,5 +13,5 @@ func (cm columnModel) Header(index int) string {
 		return ""
 	}
 
-	return cm.m.resultSet.Columns()[cm.m.colOffset+index-1]
+	return cm.m.columns[cm.m.colOffset+index-1].Name
 }

internal/dynamo-browse/ui/teamodels/dynamotableview/model.go

@@ -6,6 +6,7 @@ import (
 	"github.com/charmbracelet/lipgloss"
 	"github.com/lmika/audax/internal/dynamo-browse/controllers"
 	"github.com/lmika/audax/internal/dynamo-browse/models"
+	"github.com/lmika/audax/internal/dynamo-browse/models/columns"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/keybindings"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/dynamoitemview"
 	"github.com/lmika/audax/internal/dynamo-browse/ui/teamodels/frame"
@@ -26,35 +27,42 @@ type Setting interface {
 	IsReadOnly() bool
 }
 
+type ColumnsProvider interface {
+	Columns() *columns.Columns
+}
+
 type Model struct {
 	frameTitle      frame.FrameTitle
 	table           table.Model
 	w, h            int
 	keyBinding      *keybindings.TableKeyBinding
 	setting         Setting
+	columnsProvider ColumnsProvider
 
 	// model state
 	isReadOnly bool
 	colOffset  int
 	rows       []table.Row
+	columns    []columns.Column
 	resultSet  *models.ResultSet
 }
 
-func New(keyBinding *keybindings.TableKeyBinding, setting Setting, uiStyles styles.Styles) *Model {
+func New(keyBinding *keybindings.TableKeyBinding, columnsProvider ColumnsProvider, setting Setting, uiStyles styles.Styles) *Model {
-	tbl := table.New(table.SimpleColumns([]string{"pk", "sk"}), 100, 100)
-	rows := make([]table.Row, 0)
-	tbl.SetRows(rows)
-
 	frameTitle := frame.NewFrameTitle("No table", true, uiStyles.Frames)
 	isReadOnly := setting.IsReadOnly()
 
-	return &Model{
+	model := &Model{
 		isReadOnly:      isReadOnly,
 		frameTitle:      frameTitle,
-		table:      tbl,
 		keyBinding:      keyBinding,
 		setting:         setting,
+		columnsProvider: columnsProvider,
 	}
+
+	model.table = table.New(columnModel{model}, 100, 100)
+	model.table.SetRows([]table.Row{})
+
+	return model
 }
 
 func (m *Model) Init() tea.Cmd {
@@ -67,9 +75,15 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		m.resultSet = msg.ResultSet
 		m.updateTable()
 		return m, m.postSelectedItemChanged
+	case controllers.ColumnsUpdated:
+		m.rebuildTable(&m.table)
+		return m, m.postSelectedItemChanged
 	case controllers.SettingsUpdated:
 		m.updateTableHeading()
 		return m, nil
+	case controllers.MoveLeftmostDisplayedColumnInTableViewBy:
+		m.setLeftmostDisplayedColumn(m.colOffset + int(msg))
+		return m, nil
 	case tea.KeyMsg:
 		switch {
 		// Table nav
@@ -106,8 +120,8 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 func (m *Model) setLeftmostDisplayedColumn(newCol int) {
 	if newCol < 0 {
 		m.colOffset = 0
-	} else if newCol >= len(m.resultSet.Columns()) {
+	} else if newCol >= len(m.columnsProvider.Columns().Columns) {
-		m.colOffset = len(m.resultSet.Columns()) - 1
+		m.colOffset = len(m.columnsProvider.Columns().Columns) - 1
 	} else {
 		m.colOffset = newCol
 	}
@@ -139,14 +153,29 @@ func (m *Model) updateTableHeading() {
 func (m *Model) updateTable() {
 	m.updateTableHeading()
 	m.colOffset = 0
-	m.rebuildTable()
+	m.rebuildTable(nil)
 }
 
-func (m *Model) rebuildTable() {
+func (m *Model) rebuildTable(targetTbl *table.Model) {
+	var tbl table.Model
+
 	resultSet := m.resultSet
 
-	newTbl := table.New(columnModel{m}, m.w, m.h-m.frameTitle.HeaderHeight())
+	// Use the target table model if you can, but if it's nil or the number of rows is smaller than the
+	// existing table, create a new one
+	if targetTbl == nil || len(resultSet.Items()) > len(m.rows) {
+		tbl = table.New(columnModel{m}, m.w, m.h-m.frameTitle.HeaderHeight())
+		if targetTbl != nil {
+			tbl.GoBottom()
+		}
+	} else {
+		tbl = *targetTbl
+	}
+
+	m.columns = m.columnsProvider.Columns().VisibleColumns()
+
 	newRows := make([]table.Row, 0)
+
 	for i, r := range resultSet.Items() {
 		if resultSet.Hidden(i) {
 			continue
@@ -161,8 +190,9 @@ func (m *Model) rebuildTable() {
 	}
 
 	m.rows = newRows
-	newTbl.SetRows(newRows)
+	tbl.SetRows(newRows)
-	m.table = newTbl
+
+	m.table = tbl
 }
 
 func (m *Model) SelectedItemIndex() int {

internal/dynamo-browse/ui/teamodels/dynamotableview/tblmodel.go

@@ -3,6 +3,7 @@ package dynamotableview
 import (
 	"fmt"
 	"github.com/charmbracelet/lipgloss"
+	"github.com/lmika/audax/internal/dynamo-browse/models/itemrender"
 	"io"
 	"strings"
 
@@ -63,12 +64,12 @@ func (mtr itemTableRow) Render(w io.Writer, model table.Model, index int) {
 		sb.WriteString(metaInfoStyle.Render("⋅\t"))
 	}
 
-	for i, colName := range mtr.resultSet.Columns()[mtr.model.colOffset:] {
+	for i, col := range mtr.model.columns[mtr.model.colOffset:] {
 		if i > 0 {
 			sb.WriteString(style.Render("\t"))
 		}
 
-		if r := mtr.item.Renderer(colName); r != nil {
+		if r := itemrender.ToRenderer(col.Evaluator.EvaluateForItem(mtr.item)); r != nil {
 			sb.WriteString(style.Render(r.StringValue()))
 			if mi := r.MetaInfo(); mi != "" {
 				sb.WriteString(metaInfoStyle.Render(mi))

internal/dynamo-browse/ui/teamodels/layout/composit.go

@@ -4,18 +4,21 @@ import (
 	"bufio"
 	tea "github.com/charmbracelet/bubbletea"
 	"github.com/charmbracelet/lipgloss"
+	"github.com/mattn/go-runewidth"
+	"github.com/muesli/ansi"
+	"github.com/muesli/reflow/truncate"
 	"strings"
 )
 
 type Compositor struct {
-	background ResizingModel
+	background tea.Model
 
-	foreground   ResizingModel
+	foreground   tea.Model
 	foreX, foreY int
 	foreW, foreH int
 }
 
-func NewCompositor(background ResizingModel) *Compositor {
+func NewCompositor(background tea.Model) *Compositor {
 	return &Compositor{
 		background: background,
 	}
@@ -26,9 +29,12 @@ func (c *Compositor) Init() tea.Cmd {
 }
 
 func (c *Compositor) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
-	// TODO: allow the compositor the
+	var cmd tea.Cmd
-	newM, cmd := c.background.Update(msg)
+	if c.foreground != nil {
-	c.background = newM.(ResizingModel)
+		c.foreground, cmd = c.foreground.Update(msg)
+	} else {
+		c.background, cmd = c.background.Update(msg)
+	}
 	return c, cmd
 }
 
@@ -38,6 +44,18 @@ func (c *Compositor) SetOverlay(m ResizingModel, x, y, w, h int) {
 	c.foreW, c.foreH = w, h
 }
 
+func (c *Compositor) MoveOverlay(x, y int) {
+	c.foreX, c.foreY = x, y
+}
+
+func (c *Compositor) ClearOverlay() {
+	c.foreground = nil
+}
+
+func (c *Compositor) HasOverlay() bool {
+	return c.foreground != nil
+}
+
 func (c *Compositor) View() string {
 	if c.foreground == nil {
 		return c.background.View()
@@ -46,6 +64,7 @@ func (c *Compositor) View() string {
 	// Need to compose
 	backgroundView := c.background.View()
 	foregroundViewLines := strings.Split(c.foreground.View(), "\n")
+	_ = foregroundViewLines
 
 	backgroundScanner := bufio.NewScanner(strings.NewReader(backgroundView))
 	compositeOutput := new(strings.Builder)
@@ -58,7 +77,7 @@ func (c *Compositor) View() string {
 
 		line := backgroundScanner.Text()
 		if r >= c.foreY && r < c.foreY+c.foreH {
-			compositeOutput.WriteString(line[:c.foreX])
+			compositeOutput.WriteString(truncate.String(line, uint(c.foreX)))
 
 			foregroundScanPos := r - c.foreY
 			if foregroundScanPos < len(foregroundViewLines) {
@@ -66,7 +85,10 @@ func (c *Compositor) View() string {
 				compositeOutput.WriteString(lipgloss.PlaceHorizontal(c.foreW, lipgloss.Left, displayLine, lipgloss.WithWhitespaceChars(" ")))
 			}
 
-			compositeOutput.WriteString(line[c.foreX+c.foreW:])
+			rightStr := c.renderBackgroundUpTo(line, c.foreX+c.foreW)
+
+			// Need to find a way to cut the string here
+			compositeOutput.WriteString(rightStr)
 		} else {
 			compositeOutput.WriteString(line)
 		}
@@ -77,9 +99,33 @@ func (c *Compositor) View() string {
 }
 
 func (c *Compositor) Resize(w, h int) ResizingModel {
-	c.background = c.background.Resize(w, h)
+	c.background = Resize(c.background, w, h)
 	if c.foreground != nil {
-		c.foreground = c.foreground.Resize(c.foreW, c.foreH)
+		c.foreground = Resize(c.foreground, c.foreW, c.foreH)
 	}
 	return c
 }
+
+func (c *Compositor) renderBackgroundUpTo(line string, x int) string {
+	ansiSequences := new(strings.Builder)
+	posX := 0
+	inAnsi := false
+
+	for i, c := range line {
+		if c == ansi.Marker {
+			ansiSequences.WriteRune(c)
+			inAnsi = true
+		} else if inAnsi {
+			ansiSequences.WriteRune(c)
+			if ansi.IsTerminator(c) {
+				inAnsi = false
+			}
+		} else {
+			if posX >= x {
+				return ansiSequences.String() + line[i:]
+			}
+			posX += runewidth.RuneWidth(c)
+		}
+	}
+	return ""
+}

test/cmd/load-test-table/main.go

@@ -2,13 +2,13 @@ package main
 
 import (
 	"context"
+	"flag"
 	"fmt"
 	"github.com/aws/aws-sdk-go-v2/aws"
 	"github.com/aws/aws-sdk-go-v2/config"
 	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
 	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
 	"github.com/brianvoe/gofakeit/v6"
-	"github.com/google/uuid"
 	"github.com/lmika/audax/internal/dynamo-browse/models"
 	"github.com/lmika/audax/internal/dynamo-browse/providers/dynamo"
 	"github.com/lmika/audax/internal/dynamo-browse/services/tables"
@@ -18,9 +18,13 @@ import (
 )
 
 func main() {
+	var flagSeed = flag.Int64("seed", 0, "random seed to use")
+	var flagCount = flag.Int("count", 500, "number of items to produce")
+	flag.Parse()
+
 	ctx := context.Background()
 	tableName := "business-addresses"
-	totalItems := 500
+	totalItems := *flagCount
 
 	cfg, err := config.LoadDefaultConfig(ctx)
 	if err != nil {
@@ -53,8 +57,11 @@ func main() {
 
 	_, _ = tableService, tableInfo
 
+	log.Printf("using seed: %v", *flagSeed)
+	gofakeit.Seed(*flagSeed)
+
 	for i := 0; i < totalItems; i++ {
-		key := uuid.New().String()
+		key := gofakeit.UUID()
 		if err := tableService.Put(ctx, tableInfo, models.Item{
 			"pk":           &types.AttributeValueMemberS{Value: key},
 			"sk":           &types.AttributeValueMemberS{Value: key},
@@ -64,6 +71,12 @@ func main() {
 			"phone":        &types.AttributeValueMemberN{Value: gofakeit.Phone()},
 			"web":          &types.AttributeValueMemberS{Value: gofakeit.URL()},
 			"officeOpened": &types.AttributeValueMemberBOOL{Value: gofakeit.Bool()},
+			"colors": &types.AttributeValueMemberM{
+				Value: map[string]types.AttributeValue{
+					"door":  &types.AttributeValueMemberS{Value: gofakeit.Color()},
+					"front": &types.AttributeValueMemberS{Value: gofakeit.Color()},
+				},
+			},
 			"ratings": &types.AttributeValueMemberL{Value: []types.AttributeValue{
 				&types.AttributeValueMemberN{Value: fmt.Sprint(gofakeit.IntRange(0, 5))},
 				&types.AttributeValueMemberN{Value: fmt.Sprint(gofakeit.IntRange(0, 5))},