#*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*= # pg_geqo * # ------- = # * # Example Genetic Algorithm config file = # for the PostgreSQL * # Genetic Query Optimization (GEQO) module = # * #*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*= # Martin Utesch * Institute of Automatic Control * # = University of Mining and Technology = # utesch@aut.tu-freiberg.de * Freiberg, Germany * #*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*= # this file should be '$PGDATA/pg_geqo', but it doesn't have # to exist # comment character is '#' # # separator between recognized tag and possible value # must be white space # qs: means query size, which is the number of relations # contained in a query #=================+===================+=============================+ # RECOGNIZED TAGS | POSSIBLE VALUES | DEFAULTS | #=================+===================+=============================+ # 'Pool_Size' | positive int | 2^(qs+1) | #-----------------+-------------------+-----------------------------+ # 'Effort' | [low,medium,high] | medium | #-----------------+-------------------+-----------------------------+ # 'Generations' | positive int | 'Effort' * log2('Pool_Size')| #-----------------+-------------------+-----------------------------+ # 'Selection_Bias'| [1.50; 2.00] | 2.0 | #-----------------+-------------------+-----------------------------+ # 'Random_Seed' | positive long | time(NULL) | #=================+===================+=============================+ # 'Pool_Size' is essential for the genetic algorithm performance. # It gives us the number of individuals within one population. # # 'Effort' 'low' means integer value of 1, 'medium' 40, and 'high' 80. # # 'Generations' gives us the stopping criterion for the number # of iterations within the genetic algorithm. # # 'Selection_Bias' gives us the selective pressure within the # population. # # 'Random_Seed' is the random seed for the random() function. # You don't have to set it. # All parameters will be computed within the GEQO module when they # are not set in the pg_geqo file. # Example pg_geqo settings: # #Pool_Size 128 #Effort low #Generations 200 #Random_Seed 830518260 #Selection_Bias 1.750000