Method getBitmapFromDB

structure/bitmap_1.go:343–375

getBitmapFromDB retrieves data from the database. When isKeyCanNotExist is true, it returns an empty slice if the key doesn't exist instead of an error.

(key string, isKeyCanNotExist bool)

// getBitmapFromDB retrieves data from the database. When isKeyCanNotExist is true, it returns an empty slice if the key doesn't exist instead of an error.
func (b *BitMapStructure) getBitmapFromDB(key string, isKeyCanNotExist bool) ([]byte, uint, error) {
	if isKeyCanNotExist {
		// Get data corresponding to the key from the database
		dbData, err := b.db.Get([]byte(key))
		// Since the key might not exist, we need to handle ErrKeyNotFound separately as it is a valid case
		if err != nil && err != _const.ErrKeyNotFound {
			return nil, 0, err
		}
		// Deserialize the data into a bitmap
		bitmapArr, length, err := b.decodeBitmap(dbData)
		if err != nil {
			if len(dbData) != 0 {
				return nil, 0, err
			} else {
				bitmapArr = make([]byte, 0)
				length = 0
			}
		}
		return bitmapArr, length, nil
	} else {
		// Get data corresponding to the key from the database
		dbData, err := b.db.Get([]byte(key))
		if err != nil {
			return nil, 0, err
		}
		// Deserialize the data into a bitmap
		bitmapArr, length, err := b.decodeBitmap(dbData)
		if err != nil {
			return nil, 0, err
		}
		return bitmapArr, length, nil
	}
}

// setBitmapToDB stores the data into the database.
func (b *BitMapStructure) setBitmapToDB(key string, bm []byte, length uint) error {