Hi, Jaime, There is an option to associate a value with each data partition. More specifically, you can add a line like the following in the header section of -part.txt,
metaTags = year=2011, month=3, day=19, season=spring Later on, you can use "year", "month", "day" and "season" as regular columns. Currently, these meta-tags are treated as "string values", therefore, they might not behave as you expect. If that is the case, let me know and we can figure how to address the issue. Thanks. John On 3/18/2011 3:45 AM, Jaime Nebrera wrote: > Hi John, > >> You can use the group-by clause to get the output into the format you >> want. Say each data record has a column named month and a column >> denoting the number of bytes transferred called bytes, you can get the >> traffic volume (assumed to be total number of bytes transferred >> here) by >> a query of the following form >> >> ibis -d data-dir -q "select month, sum(bytes) where >> your-selection-criteria group by month" >> >> In factor, if you use actually use ibis.cpp to answer this query, the >> group by clause can actually be skipped if the order of group by >> operation is the same as the order of the columns in the select clause. >> Internally, ibis.cpp detects that you have requested an aggregation >> operation in the select clause and by default will perform group by on >> all column names that are not in an aggregation function. >> >> The same select clause can be passed to ibis::query object or >> ibis::table::select function as well. > > Thanks for your reply but seems matters are a bit more complex dut to > the way nprobe is using fastbit. > > The "database" is in the directory /opt/rb/shared/var/db/fastbit. > > If we execute `find /opt/rb/shared/var/db/fastbit` we get: > > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/ > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/SRC_AS > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/LAST_SWITCHED > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/SRC_TOS.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/FIRST_SWITCHED.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IN_BYTES > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/TCP_FLAGS > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IPV4_DST_MASK.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/L4_SRC_PORT.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/DST_AS.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/L4_DST_PORT > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/SRC_AS.idx > [...] > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IPV4_NEXT_HOP > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IPV4_SRC_ADDR > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IPV4_SRC_MASK > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/PROTOCOL.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/DST_AS > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IPV4_SRC_ADDR.idx > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/OUTPUT_SNMP > /opt/rb/shared/var/db/fastbit/2011/02/09/13/40/IPV4_DST_MASK > [...] > > Sadly, there is no "time" column. Time is implicit in the directory > were the file is. > > Right now, we use the fbquery command (I believe a parser provided by > Luca for ibis) to consult fastbit database this way: > > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/01 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/02 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/03 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/04 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/05 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/06 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/07 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/08 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/09 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/10 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/11 ... > fbquery -c sum(IN_BYTES) -d /opt/rb/shared/var/db/fastbit/2011/12 ... > > So we have to execute fbquery 12 times to be able to get all the dots > in the graph. > > Of course we could directly use ibis and might even consider modifying > how nprobe stores its data, but right now thats the case. > > Regards > _______________________________________________ FastBit-users mailing list [email protected] https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users
