rows_multi.go

package vertigo

// Copyright (c) 2019-2026 Open Text.
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import (
	"database/sql/driver"
	"io"
	"reflect"
)

// multiRows stitches together the results of multiple SQL statements so the
// standard database/sql iteration APIs can page through each result set.
type multiRows struct {
	sets    []*rows
	current int
}

func (m *multiRows) currentRows() *rows {
	return m.sets[m.current]
}

func (m *multiRows) Columns() []string {
	return m.currentRows().Columns()
}

func (m *multiRows) Close() error {
	var err error
	for _, set := range m.sets {
		if closeErr := set.Close(); closeErr != nil && err == nil {
			err = closeErr
		}
	}
	return err
}

func (m *multiRows) Next(dest []driver.Value) error {
	return m.currentRows().Next(dest)
}

func (m *multiRows) HasNextResultSet() bool {
	return m.current+1 < len(m.sets)
}

// NextResultSet advances to the next buffered result set, mirroring how
// database/sql exposes multi-statement results.
func (m *multiRows) NextResultSet() error {
	if !m.HasNextResultSet() {
		return io.EOF
	}
	m.current++
	return nil
}

// The column metadata helpers simply forward to the active rows instance so
// callers always see the schema for the current statement.
func (m *multiRows) ColumnTypeDatabaseTypeName(index int) string {
	return m.currentRows().ColumnTypeDatabaseTypeName(index)
}

func (m *multiRows) ColumnTypeNullable(index int) (nullable, ok bool) {
	return m.currentRows().ColumnTypeNullable(index)
}

func (m *multiRows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool) {
	return m.currentRows().ColumnTypePrecisionScale(index)
}

func (m *multiRows) ColumnTypeLength(index int) (length int64, ok bool) {
	return m.currentRows().ColumnTypeLength(index)
}

func (m *multiRows) ColumnTypeScanType(index int) reflect.Type {
	return m.currentRows().ColumnTypeScanType(index)
}