Method Last

cursor.go:66–90

Last moves the cursor to the last item in the bucket and returns its key and value. If the bucket is empty then a nil key and value are returned. The returned key and value are only valid for the life of the transaction.

()

// If the bucket is empty then a nil key and value are returned.
// The returned key and value are only valid for the life of the transaction.
func (c *Cursor) Last() (key []byte, value []byte) {
	common.Assert(c.bucket.tx.db != nil, "tx closed")
	c.stack = c.stack[:0]
	p, n := c.bucket.pageNode(c.bucket.RootPage())
	ref := elemRef{page: p, node: n}
	ref.index = ref.count() - 1
	c.stack = append(c.stack, ref)
	c.last()

	// If this is an empty page (calling Delete may result in empty pages)
	// we call prev to find the last page that is not empty
	for len(c.stack) > 1 && c.stack[len(c.stack)-1].count() == 0 {
		c.prev()
	}

	if len(c.stack) == 0 {
		return nil, nil
	}

	k, v, flags := c.keyValue()
	if (flags & uint32(common.BucketLeafFlag)) != 0 {
		return k, nil
	}
	return k, v
}

// Next moves the cursor to the next item in the bucket and returns its key and value.
// If the cursor is at the end of the bucket then a nil key and value are returned.