Phân tích tư tưởng của nhân dân qua đoạn thơ: Những người vợ nhớ chồng… Những cuộc đời đã hóa sông núi ta trong Đất nước của Nguyễn Khoa Điềm
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• Data models facilitate• Early analysis of properties, ... e.g. storage cost, querying ability,• Re-use of shared data among multiple applications• Exchange of data across organization• Conversion of data to new software/ environment• Example - Y2K crisis for year 2000Many computer software systems were developed without welldefineddata models in 1960s and 1970s. These systems used avariety of data models for representing time and date. Some ofthe representations used two digits to represent years. In late1990s, people worried that the 2 digit representation of year maylead to errorneous behaviour. For example age of a person bornin 1960 (as 60) in year...
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Book Spatial DB System
