Timesten - Query Plan

> Database > (TimesTen|TT) (In-Memory Database|IMDB)

1 - About

The query plan in TT

3 - How to

3.1 - view a plan

  • with an explain
  • in the SYS.PLAN table (after a prepare or an explain)
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3.2 - modify an execution plan

Applications can modify an execution plan by providing hints to the optimizer. Hints are specified by calls to one of the TimesTen optimizer built-in procedures which all start with ttOpt.

  • ttOptSetFlag—Sets certain optimizer flag See for a list of flag.
  • ttOptSetOrder—Enables an application to specify the table join order.
  • ttOptUseIndex—Enables an application to specify that an index be used or to disable the use of certain indexes.
  • ttOptClearStats, ttOptEstimateStats, ttOptSetColIntvlStats, ttOptSetTblStats, ttOptUpdateStats—Manipulate statistics that the TimesTen Data Manager maintains on the application's data that are used by the query optimizer to estimate costs of various operations.

See the last Timesten reference documentation for the built-in documentation.

4 - Operations

4.1 - full table scan

  • TblLkSerialScan - full table scan with Table lock
  • RowLkSerialScan - full table scan with Row Lock