Oracle SQL Profiler is a powerful query optimization tool to fine-tune SQL queries. The tool allows you to easily check and analyze query performance in Oracle, quickly detect bottlenecks in query execution and
Hence to tune database management systems it is necessary to tune database in a cost effective manner for which different optimization techniques have been used. To minimize the cost there is a need to build self-managing database system which can continually monitor performance at the time of ...
To avoid this scenario, Oracle Database can automatically create temporary tables for the query results and store them in memory for the duration of the cursor. For complex operations such asWITHclause queries, star transformations, and grouping sets, this optimization enhances the materialization of...
For example, if you upgrade the Oracle Database 11g from Release 1 (11.1.0.7) to Release 2 (11.2.0.2), then the default value of the OPTIMIZER_FEATURES_ENABLE parameter changes from 11.1.0.7 to 11.2.0.2. This upgrade results in the optimizer enabling optimization features based on 11.2.0.2...
Compare PostgreSQL partitioning, replication, query optimization, and data security in this comprehensive open source database showdown with MySQL.
Acceptable performance— A query takes 10 minutes to run and the user wants it to run in one minute; that seems like a reasonable disparity and an achievable goal for optimization. However, if the query takes overnight and the user thinks it should run in one minute, then it may be more...
Query Optimization Highlights Chapter 16 (intro), 16.1 (skim), 16.2 (skim) 12/8/97 Naïve Query Processing SELECT LNAME FROM EMPLOYEE, DEPARTMENT WHERE DNO=DNUMBER AND SALARY>45000 AND DNAME="Software Support"; Naively, this is 1 Cartesian product, followed by 3 selects, followed by one...
8.2 SQL Optimization On MPP Databases The exponential growth in the amount of data being stored and queried has translated into a wider usage of Massively Parallel Processing (MPP) systems such as Tera- data [27], Oracle's Exadata [31], Netezza [25], Pivotal Green- plum Database [20], ...
L can be solved in polynomial time by an oracle machine with an oracle for H. That the covering queries optimization problem is NP-hard can be proven by reduction from the Set Cover problem. As also is known to those having ordinary skill in the art, the Set Cover problem is a classica...
Techniques for query optimization for group-by extensions and distinct aggregate functions are provided. A query has an extended group-by clause with an extended group-by operator a