[update] bindplan sticked with a columnfilter

db.go

@@ -183,7 +183,7 @@ func (m *DbMap) AddTableWithNameAndSchema(i interface{}, schema string, name str
 		}
 	}
 
-	tmap := &TableMap{gotype: t, TableName: name, SchemaName: schema, dbmap: m}
+	tmap := NewTableMap(t, name, schema, m)
 	var primaryKey []*ColumnMap
 	tmap.Columns, primaryKey = m.readStructColumns(t)
 	m.tables = append(m.tables, tmap)

gorp_test.go

@@ -1586,6 +1586,21 @@ func TestColumnFilter(t *testing.T) {
 	if inv2.IsPaid {
 		t.Error("IsPaid shouldn't have been updated")
 	}
+
+	// update isPaid field only
+	_updateColumns(dbmap, func(col *gorp.ColumnMap) bool {
+		return col.ColumnName == "IsPaid"
+	}, inv1)
+
+	inv2 = &Invoice{}
+	inv2 = _get(dbmap, inv2, inv1.Id).(*Invoice)
+	if inv2.Memo != "c" {
+		t.Errorf("Expected column to be updated (%#v)", inv2)
+	}
+	if !inv2.IsPaid {
+		t.Error("IsPaid should have been updated")
+	}
+
 }
 
 func TestTypeConversionExample(t *testing.T) {

table.go

@@ -16,6 +16,7 @@ import (
 	"fmt"
 	"reflect"
 	"strings"
+	"sync"
 )
 
 // TableMap represents a mapping between a Go struct and a database table
@@ -31,18 +32,30 @@ type TableMap struct {
 	uniqueTogether [][]string
 	version        *ColumnMap
 	insertPlan     bindPlan
-	updatePlan     bindPlan
 	deletePlan     bindPlan
 	getPlan        bindPlan
 	dbmap          *DbMap
+
+	updatePlan  map[string]bindPlan
+	muForUpdate sync.Mutex
+}
+
+func NewTableMap(t reflect.Type, name string, schema string, dbmap *DbMap) *TableMap {
+	return &TableMap{
+		gotype:     t,
+		TableName:  name,
+		SchemaName: schema,
+		dbmap:      dbmap,
+		updatePlan: map[string]bindPlan{},
+	}
 }
 
 // ResetSql removes cached insert/update/select/delete SQL strings
 // associated with this TableMap.  Call this if you've modified
 // any column names or the table name itself.
 func (t *TableMap) ResetSql() {
 	t.insertPlan = bindPlan{}
-	t.updatePlan = bindPlan{}
+	t.updatePlan = map[string]bindPlan{}
 	t.deletePlan = bindPlan{}
 	t.getPlan = bindPlan{}
 }

table_bindings.go

@@ -15,6 +15,7 @@ import (
 	"bytes"
 	"fmt"
 	"reflect"
+	"strings"
 	"sync"
 )
 
@@ -167,13 +168,35 @@ func (t *TableMap) bindInsert(elem reflect.Value) (bindInstance, error) {
 
 	return plan.createBindInstance(elem, t.dbmap.TypeConverter)
 }
+func (t *TableMap) signatureForColumns(colFilter ColumnFilter) string {
+	var tokens []string
+	for y := range t.Columns {
+		col := t.Columns[y]
+		if colFilter(col) {
+			tokens = append(tokens, col.ColumnName)
+		}
+	}
+	return strings.Join(tokens, ",")
+}
 
 func (t *TableMap) bindUpdate(elem reflect.Value, colFilter ColumnFilter) (bindInstance, error) {
+	var key string
 	if colFilter == nil {
 		colFilter = acceptAllFilter
+		key = "default" // if we wants to update all columns, make it simple
+	} else {
+		key = t.signatureForColumns(colFilter)
+	}
+
+	t.muForUpdate.Lock()
+	_, ok := t.updatePlan[key]
+	if !ok {
+		t.updatePlan[key] = bindPlan{}
 	}
+	updatePlan := t.updatePlan[key]
+	t.muForUpdate.Unlock()
 
-	plan := &t.updatePlan
+	plan := &updatePlan
 	plan.once.Do(func() {
 		s := bytes.Buffer{}
 		s.WriteString(fmt.Sprintf("update %s set ", t.dbmap.Dialect.QuotedTableForQuery(t.SchemaName, t.TableName)))