Comparison of bind variable peeking in Oracle with parameter sniffing in SQL Server Continue Reading
This blog post is a short observation on assumptions that Oracle and SQL server optimizers make for estimating cardinality of a rowset obtained after applying an equality predicate which contains different columns of the same table. Continue Reading
Comparing efficiency of IOT in Oracle with Clustered Index in SQL Server. Continue Reading
Disjunctive subqueries are the subqueries which are applied to the or operator. Alternatively, these queries can be rewritten to use the union all operator which may be a more efficient way to retrieve the records from the database. This blog post compares the efficiency of SQL Server and Oracle optimizer when dealing with the transformations of disjunctive subqueries.
Not always the cheapest execution plan gets chosen. This blog post describes such an edge case in SQL Server and Oracle. Continue Reading