Hi, The name of the coercions optimizer in the codes array in opt_wrapper.c is wrong (currently it's "coercion"), and so it is never run. This patch fixes: diff -r 6e9b305e92e2 monetdb5/optimizer/opt_wrapper.c --- a/monetdb5/optimizer/opt_wrapper.c Sun Feb 10 17:39:23 2013 +0100 +++ b/monetdb5/optimizer/opt_wrapper.c Tue Feb 12 11:33:20 2013 +0000 @@ -84,7 +84,7 @@ {"aliases", &OPTaliasesImplementation}, {"centipede", &OPTcentipedeImplementation}, {"cluster", &OPTclusterImplementation}, - {"coercion", &OPTcoercionImplementation}, + {"coercions", &OPTcoercionImplementation}, {"commonTerms", &OPTcommonTermsImplementation}, {"compression", &OPTcompressionImplementation}, {"costModel", &OPTcostModelImplementation}, Regards, Pete