Please help. What program to open pdb format.

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Downloaded E-book, whish is pdb format. What program I should usr to open it. TVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。& v. Z: L" ~* [4 {/ _5 ]
Thank you