Informix has Automated Update Statistics built into the server. Update Statistics collects metrics to enable the server to run your SQL faster. How do you monitor what tables and indexes need to have the statistics updated and manage Automated Update Statistics (AUS)?
How does the Informix SQL Optimizer choose which index or table or access method to use when running your SQL? This presentation will focus on how to view and understand the SQL Explain plan to see how your SQL is executed. The SQL Explain plan will provide times for each step in your process.
This presentation will focus on Best Practices for Informix database indexes. Every table should have at least one index, and managing indexes is an integral part of a DBA's task and time. Indexing is one method to optimize the performance of a database by reducing the number of disk reads when a query is executed. An index is a structure which is used to locate and access a row in a database table quickly. Indexes are used to enforce uniqueness, primary, and foreign keys and constraints. Indexes can also be a source of problems in a database and may slow performance down when misused.
Art Kagel developed and maintains the popular open source utility dostats to enable you to automate and keep up to date catalog statistics and data distribution that the Informix Optimizer needs in order to select the best method of running your SQL statements. He will describe how it works, how to compile it on several platforms, and why you should upgrade to the latest version. He will also discuss the Informix Automated Update Statistics (AUS) and how that compares to dostats.