Anurag, Yes you can. Copy command just issues the query you supply it with and you can force it to do parallel query with hints (or otherwise). The question however is: will it speed up your copy process? What is the bottleneck? Reading the data from the source-table, or something else? What would you ideally want to be the bottleneck of a large copy-process? A couple of weeks ago I was challenged to copy a 270 Gbyte table from one database to another. Given the 100 Mbit/second ethernet in between the two databases, this could not be done any faster than a little less than 6 hours. I did some testing and eventually ended up with a copy-process that would have the network as its bottleneck. It turned out that just having the process perform a (non-parallel) full table scan would generate rows at a rate that the network could not keep up with. Point being: forcing it to perform a parallel scan would not speed up any further. Here's what I did (with thanks going to Alex Gorbachev): In the database session that performs the 'from/using' query of the copy-command: alter session set "_serial_direct_read"=true; alter session set db_file_multiblock_read_count=128; -- Increased from 64 The _serial_direct_read prevented me from hitting a 'snapshot too old' error. Apparently (though still not 100% sure) it prevents 'block cleanouts' that cause block writes, which in turn cause rollback segment allocation. I used a database login-trigger to perform these two alter session statements in the session that performs the 'from/using' query. Then (of course) in SQLPlus I set the arraysize to its maximum possible value: set arraysize = 5000 The query on the source table was performing a simple full table scan. Copy commit was set to zero: i.e. commit once at the end of the copy process. And finally: no indexes or constraints were present on the destination-table (which was an empty table upon start of the copy-process). The copy process took a little under 6 hours. It was copying from a 9i database to an 11G database. After the copy-process it took another 6-7 hours to build indexes and enable constraints. Toon On 6/16/08, Anurag Verma <anuragdba@xxxxxxxxx> wrote: > > Hi, > > > Can we use parallel degree option to copy a table from one database to > another? > > I have 2 Oracle 9i databases and have to copy some huge amount of data. > > Thinking of various options and want to know whether I can implement > parallel option (in the same way what we do with Parallel DMLs). > > This is what the COPY syntax I am seeing from sqlplus utility. > > usage: COPY FROM <db> TO <db> <opt> <table> { (<cols>) } USING <sel> > <db> : database string, e.g., hr/your_password@d:chicago-mktg > <opt> : ONE of the keywords: APPEND, CREATE, INSERT or REPLACE > <table>: name of the destination table > <cols> : a comma-separated list of destination column aliases > <sel> : any valid SQL SELECT statement > > > -- > Thanks, > > Anurag Verma, > Database Administrator > ERCOT(Electric Reliability Council of Texas), > Texas 76574 > -- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- Toon Koppelaars RuleGen BV +31-615907269 toon_at_rulegen_dot_com www_dot_rulegen_dot_com Author: "Applied Mathematics for Database Professionals"