[mellody]

Here's YUI, Tsuji Shion, and Kana Nishino 1st album DVD Tracklist, just for comparison :

Spoiler:

YUI - From Me To You
DVD Tracklist
1. feel my soul (PV) (1st single)
2. Tomorrow's way (PV) (2nd single)
3. LIFE (PV) (3rd single)
4. TOKYO (PV) (4th single)

Tsuji Shion - Catch!
DVD Tracklist
1. Candy kicks (PV) (1st single)
2. Sky chord ~Otona ni Naru Kimi e~ (Sky chord ～大人になる君へ～) (PV) (2nd single)
3. M/elody (PV) (3rd single)
4. Hoshii Mono (ほしいもの) (PV) (4th single)
5. Tsuji Days ~Debut Kara no Kiseki~ (つじでいず ～デビューからの軌跡～)
6. Tsuji Radio Special♪ ~Self Liner Note Eizou~ (つじらじお スペシャル♪～セルフライナーノーツ映像～)

Nishino Kana - LOVE one.
DVD Tracklist
1. I (PV) (1st single)
2. glowly days (PV) (2nd single)
3. Style. (PV) (3rd single)
4. MAKE UP (PV) (4th single)
5. Tookutemo feat. WISE (PV) (5th single)
6. Kimi ni Aitaku Naru Kara (PV) (6th single)

Since Nishino Kana isn't singer-songwriter, she has 6 singles before an album, YUI and Tsuji Shion are singer-songwriter, both of them has 4 singles before album debut.

The reason why I choose those 3 names because they are under Sony as well. You can try another artists under Sony label to compare too.