| Tables From Tables |
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| There
are five fundamental operations |
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| on
tables to create tables: |
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| • | Select -- pick rows from a
table |
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| • | Project -- pick columns from a table |
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| • | Union -- combine two tables w/like columns |
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| • | Difference -- remove one table from another |
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| • | Product -- create “all pairs” from two tables |
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| Though
not primitive “Join” is usually included |