ADBE014E EXPLAIN table already exists. When no EXPLAIN table is specified and the action field has CREATE, the stored procedure attempts to create three EXPLAIN tables, PLAN_TABLE, DSN_STATEMNT_TABLE, and DSN_STATEMENT_CACHE_TABLE. However, at least one of these tables already exist and will not be created. Specify UPGRADE instead of CREATE in the action field or specify the EXPLAIN tables that do not exist when the action field has CREATE.

  ExplanationAt least one of the selected EXPLAIN tables will not be created, because it
   already exists.

  System action
Processing
                                                  stops.

  User responseSpecify UPGRADE or specify EXPLAIN tables that do not already
   exist.