In the preferences I would like to better control the number of scenarios. For example; generate no more than n scenarios. Real problem when you end up generating 600+ of them.
You can control the number of SQL alternatives that are created by the optimization process using the Optimizer/Quota page. In version 7.0, this is found under the Batch Optimizer options. In version 7.2, you will find it under the Tuning Lab options. Setting this quota controls both the Batch Optimizer and the Tuning Lab optimization processes.
On the Intelligence Level page of the Optimizer preferences, if you select Predefined, then the quota value is set for you. The higher the level the more higher the quota values are set so the higher the level, the more alternatives may be generated.
On the Intelligence Level page, if you select Custom, then you can set the quota levels yourself.
The Syntax transformation quota specifies the maximum number of SQL statements generated by applying the syntax transformation rules.
The Hints quota specifies the maximum number of SQL statements that may be created when the Oracle optimization hints are applied. This value determines the number of SQL alternatives that are generated by applying the Oracle hints to the original SQL and the SQL alternatives that were created by transforming the SQL syntax.
The Syntax transformation quota and the Hints quota are combined to get the Total Quota.