Queries: The Sequel
Most SQL solutions involve one SELECT or ACTION statement, but sometimes a more complex approach is needed. Subqueries, also known as subselects,and Parameter queries are both appropriate solutions in the right situations. A subquery combines two queries by embedding a SELECT statement within another. A subquery isn’t necessarily any faster than two fixed queries, but, once you start executing queries programmatically, you may find that subqueries are a bit easier to work with because you’ll need to execute only one query instead of two. In addition, some developers actually find subqueries easier to write once they’re familiar with the syntax.
KeywordsSelect Statement Specific Time Period Parameter Expression Action Query Delete Statement
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