Wednesday, January 23, 2013

TIL: What makes a query relational?

1.The relational result set does not any order by default. If your query has an ORDER BY clause, your resultset ceases to be relational.
2. For any query to be relational, it must satisfy a number of requirements - No ORDER BY clause, All attributes must have names, all attributes must be unique, duplicates must not appear in the result.