Please help (backup -restore)

Dear Sir,
I need your help.
I am new to postgresql 7.3.2 .

My requirement is row level incermental backup with image & movies
(datatype bytea).

Ex: I have tables say sports,music,film.
In all those tables I have test data aswell as bytea data(image &
movie).
If I want to take backup conditionaly for specific tables say for
sprots & music after certain date with where condition
(like export where in oracle).
Is ther any wayy out Please ..please help me.

Thanks & Best Regards

Ranjan

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