SAP SQL Anywhere
SQL Anywhere Whitepapers - A Selected List
The following are links to some useful SQL Anywhere whitepapers (both business- and technical-oriented) that are available in the SQL Anywhere SCN Community. You can browse the complete list of documents here.
- Migrating SQL Anywhere database applications to ASE. Some Sybase customers may need to explore the possibility of migrating one or more SQL Anywhere applications to ASE servers to consolidate their server environments, or to take advantage of some specific ASE product features. This white paper outlines the major differences between the two systems, specifically comparing SQL Anywhere 12.0.1 with ASE 15.5.
- SQL Anywhere I/O Requirements for Windows and Linux. Database servers need to be able to guarantee that data gets to stable storage to ensure that committed transactions persist and to properly implement recovery in case of power loss. Operating systems and storage devices cache and reorder write operations in order to improve performance. Running a database server on an improperly configured system can lead to data loss and file corruption. This document aims to provide the background necessary to understand the durable storage requirements and I/O semantics of SQL Anywhere.
- Capacity Planning with SQL Anywhere:We present an overview of issues to consider when designing a performance evaluation of SQL Anywhere. In particular, we outline potential pitfalls when designing a benchmark based on a specific database application. We address issues related both to the construction of a model database instance, and a model application workload, and outline an approach to construct a model of performance to determine the relative importance of various performance factors, such as database cache size and the server multiprogramming level. The paper contains several examples illustrating the potential of negative scalability that can occur when executing concurrent requests in an SMP environment, and how these scenarios can be generated easily by artificial contention caused by poorly-defined workloads.
- Diagnosing Application Performance Issues with SQL Anywhere: This whitepaper presents a method for troubleshooting performance problems in SQL Anywhere, with a focus on version 10. It describes the nature of performance problems and classifies them into categories of CPU-bound, I/O-bound, and concurrency-bound problems. We describe the steps a DBA should take to classify a performance problem, the tools provided in the product to examine the problem, and the analysis that must be done to resolve it.
- Analytic Functions in SQL Anywhere:This whitepaper includes details and examples of the OLAP support in the 10.0.0 release of SQL Anywhere.
- Optimizing SQL Anywhere Performance Over a WAN : This document discusses tuning performance for an Adaptive Server Anywhere network server that is running over a WAN. TCP/IP is the protocol of choice for WAN implementations and is the main focus of this document. Note that network performance tuning is an iterative process of determining what works best with a particular application and network. An older version of this document can be found here: Optimizing Adaptive Server Anywhere Performance Over a WAN
- Mixed-Typed Comparisons In Adaptive Server Anywhere 9: This document describes the semantics of evaluating comparisons where the comparands have different data types. It describes the algorithms Adaptive Server Anywhere 9 uses to estimate selectivity, choose indexes, and evaluate these comparison predicates. In particular, the following issues are discussed: (1) What semantics are used for a comparison with arguments of different types? and (2) When can Adaptive Server Anywhere use an index if the type of the indexed column is not the same as the comparand?
- Semantics and Compatibility of Transact-SQL Outer Joins: Transact-SQL outer joins are specified using the special comparison operators '* ='and '= *'. Using one (or more) of these operators in a query specifies an outer join between two tables in the From clause, though the semantics of such queries can be unclear. This is because TSQL outer join semantics were never formally defined, and in older releases of Adaptive Server Enterprise and Adaptive Server Anywhere the results of TSQL outer join queries could depend upon the access plan chosen by the optimizer. This iAnywhere Solutions' Technical White Paper describes the semantics of TSQL outer joins in detail, and in particular outlines the differences in support for TSQL outer joins between ASE and ASA. Because of these differences, iAnywhere Solutions recommends that customers use ANSI outer join syntax, rather than Transact-SQL outer join syntax, in their applications.
- Improving Performance in SQL Anywhere: So you want to improve performance? Join the club. Performance is an issue on everyone's agenda, since faster and better mean more effective, and ultimately, more profitable. While Adaptive Server Anywhere is designed to give you great performance right out of the box with very little intervention on your part, there is always room to fine tune your database to give you even better results.