Do you want to (a) just empty out the contents for all dates but keep the table ? or (b) completely remove the table from the database?
If (b) -- you just need to find all directories with the table name under each partition and delete them
if (a) -- create a zero row in-memory copy of the table, and write to all partitions
for (a) code would look something like (note, this is untested code)
// assumes table name is 'someTable' - and root of hdb is set in var 'dbRoot'
q) (` sv'.Q.par[dbRoot;;`someTable]'[date],\:`) set\: .Q.en[dbRoot] delete date from select from someTable where date=max date, i = -1
The above code will (working right to left)
1) select 'someTable' from disk, row -1 (creates a 0 row table)
2) deletes date column
3) enumerates symbol columns (although this is actually unnecessary in the above case, as all symbol columns will be enumerated as we've just selected them from disk)
4) constructs splay paths for the table for each of the dates (see
.Q.par) and saves the new empty table to each splay
Mohammad Noor
