||SQL Execution Plans: Informix versus SQL Server and Oracle|
||Alex Cheng is an IT veteran starting his professional
career as a programmer in 1976 at a large bank, which is
now part of Bank of America. From there, he worked as a
developer, system analyst, database administrator,
project leader at several large companies including
ExxonMobil, Shell Oil, EDS and Compaq Computer.
Currently, he is the manager of Database Architecture and
Administration at Insperity.
Alex received his masters degree from University of South
Carolina at Columbia. He is also the holder of ICDBA (IBM
Certified DBA), MCDBA (Microsoft Certified DBA), MCSE
(Microsoft Certified Systems Engineer), CDP (Certificate
in Data Processing from Institute of Certification for
Computer Professionals) and CTM (Certified Toast Master).
He has been a frequent and popular speaker at the IIUG
Conference, IDUG (International DB2 Users Group)
Conference, PASS Summit (Microsoft SQL Server Conference)
and ISUG (International Sybase Users Group) Conference.|
|SQL execution plans are arguably the most powerful tools to
tune for high performance in relational database management
systems (DBMS). Informix is an enterprise-strength DBMS.
For large companies using Informix, there are good chances
that they also use SQL Server and Oracle. However, SQL
execution plans are quite different among these three DBMS.
This session is specially prepared for those DBAs and
database developers using them.
A good example of major differences in SQL execution plans
among Informix, SQL Server and Oracle is how they handle the
missing indexes. Informix automatically creates the needed
index in run time for session use only and marks it as an
Ďauto indexí on SQL execution plans. SQL Server produces a
tuning advice on the missing index, but doesnít create the
index automatically. Oracle doesnít produces a tuning
advice, nor create the index automatically.
This session will focus on three major areas: 1) how to use
SQL execution plans in Informix, SQL Server and Oracle; 2)
how to explain SQL execution plans from these three DBMS and
their major differences; 3) how to use SQL execution plans
for performance tuning. The key areas 2 and 3 are closely
related because if you donít know how to explain SQL
execution plans correctly, then you cannot do performance
tuning work efficiently. The session will have a live demo
in using SQL execution plans for tuning in Informix if
session time and Internet connection at conference site