meiyifei

You need to set a parameter to support aggregate push down and join push down #alter system set clickhousedb_fdw.join_pushdown_safe=on; #select pg_reload_conf();

It depends on this value:max_result_bytes=14000000; sprintf(url, "Driver={%s};url=http://%s:%s@%s:%d/query?database=%s&max_result_bytes=14000000&buffer_size=3000000;",driver,user,pass,host,port,dbname); We need to modify clickhouse-client.cpp and then recompile clickhouse_fdw.