Miscellaneous

Following is a list of miscellaneous enhancements introduced in SQL Anywhere version 11.0.1.

  • Improved performance for simple, inexpensive statement execution   The cost of generating an execution plan for statements with inexpensive execution times can sometimes be greater than the cost of executing the statement. With the following enhancements, SQL Anywhere now recognizes an expanded class of simple statements with inexpensive execution times and allows them to bypass the optimizer.

    For more information, see Eligibility to skip query processing phases.

    • New FORCE NO OPTIMIZATION clause   Previously, all statements that required cost-based optimization were processed by the optimizer. With the addition of the FORCE NO OPTIMIZATION clause, you can specify that you want the statement to bypass the optimizer. If the statement is too complex to process in this way—possibly due to the setting of database options or characteristics of the schema or query—the statement fails and the database server returns an error.

      The following statements support the new FORCE NO OPTIMIZATION clause:

    • New connection properties  

      • QueryBypassedCosted
      • QueryBypassedHeuristic
      • QueryBypassedOptimized
      • QueryOpened
      • QueryDescribedBypass
      • QueryDescribedOptimizer
      • StatementDescribes
      • StatementPostAnnotates
      • StatementPostAnnotatesSimple
      • StatementPostAnnotatesSkipped

    • New database properties  

      • Prepares
      • QueryBypassedCosted
      • QueryBypassedHeuristic
      • QueryBypassedOptimized
      • QueryOpened
      • QueryDescribedBypass
      • QueryDescribedOptimizer
      • StatementDescribes
      • StatementPostAnnotates
      • StatementPostAnnotatesSimple
      • StatementPostAnnotatesSkipped

    • New Optimization Method field   The Optimization Method field has been added to the Optimizer Statistics section of the graphical plan. The field returns the execution strategy chosen by the query optimizer. See Execution plan components.

  • Prevent a database server from becoming the default database server   The -xd server option prevents a database server from listening on the default TCP port, and prevents the database server from becoming the default database server. See -xd dbeng12/dbsrv12 server option.

  • Support for parallel archive backups   The SQL Anywhere database server now supports parallel backups for server-side archive backups. Parallel database backups take advantage of physical I/O to perform read and write operations in parallel, instead of sequentially, which improves performance.

    Two new clauses have been added to the BACKUP DATABASE statement to support parallel archive backups:

    • WITH CHECKPOINT LOG [ NO ] COPY
    • MAX WRITE { n | AUTO }

    Version 11.0.0 and earlier database servers cannot restore archive backups generated with version 11.0.1 database servers. Version 11.0.1 database servers can restore backups produced by older database servers.

    See BACKUP statement.

  • Running Developer Edition and Evaluation database servers on Mac OS X   You can now automatically start Developer Edition and Evaluation Edition database servers from the administration tools on Mac OS X.