Ask database

Dear master

Now I'm using PostgreSQL server but my company has plan to
change PostgreSQL to another database "hand made" by
software hous systems. Can you explain to me what kind of
factors to class list database engine. I mean how can I
compare for each database engine. Because I want to
explain that for someone who don't know database at all.
For example : from compatibility side or the other side

TIA
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Netkuis Instan untuk wilayah Bandung (kode area 022) - SD,SMP,SMA berhadiah total puluhan juta rupiah... periode I
dimulai1 April 2004 
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