Merge pull request #1487 from ydb-platform/allow-skip-sql-fields

Allowed skip struct field in ScanStruct by tag -

Author: asmyasnikov

CHANGELOG.md

@@ -1,3 +1,5 @@
+* Allowed skip column for `ScanStruct` by tag `-` 
+
 ## v3.81.4
 * Returned `topicwriter.ErrQueueLimitExceed`, accidental removed at `v3.81.0`
 

internal/query/scanner/struct.go

@@ -56,6 +56,10 @@ func (s StructScanner) ScanStruct(dst interface{}, opts ...ScanStructOption) (er
 	existingFields := make(map[string]struct{}, tt.NumField())
 	for i := 0; i < tt.NumField(); i++ {
 		name := fieldName(tt.Field(i), settings.TagName)
+		if name == "-" {
+			continue
+		}
+
 		v, err := s.data.seekByName(name)
 		if err != nil {
 			missingColumns = append(missingColumns, name)

internal/query/scanner/struct_test.go

@@ -618,6 +618,37 @@ func TestStructNotFoundColumns(t *testing.T) {
 	require.ErrorIs(t, err, ErrColumnsNotFoundInRow)
 }
 
+func TestStructSkippedColumns(t *testing.T) {
+	scanner := Struct(Data(
+		[]*Ydb.Column{
+			{
+				Name: "A",
+				Type: &Ydb.Type{
+					Type: &Ydb.Type_TypeId{
+						TypeId: Ydb.Type_UTF8,
+					},
+				},
+			},
+		},
+		[]*Ydb.Value{
+			{
+				Value: &Ydb.Value_TextValue{
+					TextValue: "test-a",
+				},
+			},
+		},
+	))
+
+	var row struct {
+		A string
+		C string `sql:"-"`
+	}
+	err := scanner.ScanStruct(&row)
+	require.NoError(t, err)
+	require.Equal(t, "test-a", row.A)
+	require.Empty(t, row.C)
+}
+
 func TestStructWithAllowMissingColumnsFromSelect(t *testing.T) {
 	scanner := Struct(Data(
 		[]*Ydb.Column{