======================== unified (from filesystem) ========================
                                         'bitrate'  '128.0'
                                        'duration'  '106'
                                          'artist'  'Frédéric Chopin'
                                     'text_people'  ''
                                         'release'  'Essential Classics (disc 2)'
                                           'title'  "Waltz No. 6 'Minute Waltz'"
                                           'quals'  ("['Q-HAP-2', 'Q-LOCALNESS-1', 'Q-JZFKS-1', 'Q-UNU-1', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'Q-PLAY-3', 'q-syn-1', 'q-bass-1', 'q-busy-2', 'q-grit-2', "
 "'q-chart-3', 'q-drums-1', 'q-other-1', 'q-vocals-1', 'q-mixbeat-1', "
 "'Q-PIANO-4']")
                                      'lastfmtags'  "['instrumental', 'polish', 'piano', 'romantic', 'classical']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  '1'
                                      'tracktotal'  ''
                                            'date'  '1940'
                                        'comments'  ''
                                           'genre'  'prerock-classical or classical instruments'
                                             'bpm'  '145.163'
                                             'key'  '4B'
                                        'acoustid'  ''
rest: ''

======================== rawer (from filesystem) ========================

'TALB' (Album/Movie/Show title)                     'Essential Classics (disc 2)'
'TBPM' (BPM (beats per minute))                     '145.163'
'TCON' (Content type, a.k.a. Genre)                 'prerock-classical or classical instruments'
'TDRC' (Recording time)                             '1940'
'TIT2' (Title/songname/content description)         "Waltz No. 6 'Minute Waltz'"
'TKEY' (Initial key)                                '4B'
'TPE1' (Lead performer(s)/Soloist(s))               'Frédéric Chopin'
'TRCK' (Track number/Position in set)               '1'
'TXXX:Q-HAP'                                        '2'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '1'
'TXXX:Q-LOCALNESS'                                  '1'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-PIANO'                                      '4'
'TXXX:Q-PLAY'                                       '3'
'TXXX:Q-UNU'                                        '1'
'TXXX:lastfmtags'                                   ['instrumental', 'polish', 'piano', 'romantic', 'classical']
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '2'
'TXXX:q-chart'                                      '3'
'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '2'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '1'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '1'
'TXXX:replaygain_track_gain'                        '+1.76 dB'
'TXXX:replaygain_track_peak'                        '0.730858'

========================== row from database ==========================
                                              'id'  176689
                                            'path'  /data/Music/Bulk/00instruments-classical/Unsorted/Frederic Chopin__Greatest Hits (Ref. Gold Disk 2)__10 - Waltz #6 (Minute Waltz).mp3
                                         'working'  None
                                         'bitrate'  128
                                    'duration_sec'  106
                                           'genre'  prerock-classical or classical instruments
                                        'filesize'  1711935
                                           'mtime'  1637329808
                                   'redo_metaread'  0
                                        'rest_str'   00instruments classical Unsorted Frederic Chopin__Greatest Hits (Ref. Gold Disk 2)__10 #6 (Minute Waltz) prerock classical or classical instruments
                                      'tag_artist'  Frédéric Chopin
                                     'tag_release'  Essential Classics (disc 2)
                                       'tag_title'  Waltz No. 6 'Minute Waltz'
                                             'bpm'  145.163
                                    'search_title'  '6':4 'minute':5,6 'no':2,3 'waltz':1,7
                                   'search_artist'  'chopin':3 'frederic':1,2
                                  'search_release'  '2':5,6 'classics':2 'disc':3,4 'essential':1
                                     'search_rest'  '00instruments':1 '10':13,15 '2':12,14 '6':16,17 'chopin':5 'classical':2 'disk':11 'frederic':4 'gold':10 'greatest':6 'hits':7 'instruments':24 'minute':18,19 'or':23 'prerock':22 'ref':8,9 'unsorted':3 'waltz':20,21
                                    'search_combo'  '00instruments':17 '10':29,31 '2':15C,16C,28,30 '6':4A,32,33 'chopin':10B,21 'classical':18 'classics':12C 'disc':13C,14C 'disk':27 'essential':11C 'frederic':8B,9B,20 'gold':26 'greatest':22 'hits':23 'instruments':40 'minute':5A,6A,34,35 'no':2A,3A 'or':39 'prerock':38 'ref':24,25 'unsorted':19 'waltz':1A,7A,36,37
                                    'tag_tracknum'  1
                                      'num_images'  0
                                             'key'  4B
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-1', 'Q-LOCALNESS-1', 'q-mixbeat-1', 'Q-PIANO-4', 'Q-OLDST-1', 'Q-UNU-1', 'Q-JZFKS-1', 'q-busy-2', 'q-drums-1', 'q-syn-1', 'q-chart-3', 'q-other-1', 'Q-HAP-2', 'Q-PLAY-3', 'q-bass-1', 'q-grit-2']
                                      'lastfmtags'  ['instrumental', 'polish', 'piano', 'romantic', 'classical']
                                        'tag_date'  1940
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1637329808.155093  (2021-11-19 14:50:08)
                             'size'  1711935