In oracle SELECT clause is to avoid the use '*'

Others 2019-07-03 10:57:28 views: null

When you want to list all COLUMN in the SELECT clause, the use of dynamic SQL column reference to '*' is a convenient way.

Unfortunately, this is a very inefficient method. In fact, ORACLE in parsing process, will '*' in turn is converted to all

Column names, this work is done by querying the data dictionary, which means that the more time-consuming.

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Origin www.cnblogs.com/fanweisheng/p/11124279.html

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