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Unformatted text preview: With clause With clauses can be implemented using subqueries when the with clause is unavailable (i.e. when using MySQL). Heres an example that corresponds to slide 3.43: Select acct_num, balance from account where balance >= all (select balance from account); Views Table 1 Views vs. Base Tables Type Description Base Table Named table, real, autonomous Views Named table, virtual, derived tables Virtual tables do not keep a separate, permanent stored copy of the underlying tables data; it is generated each time the view is accessed. If you drop an underlying table, the view does not survive either. You can only update a view that is a column subset of a base table. Views that involve joins, aggregate functions, etc. cannot be updated....
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This note was uploaded on 01/25/2010 for the course CSC 4402 taught by Professor Staff during the Fall '08 term at LSU.
- Fall '08