Yes, you can change the compressor as you want(use alter table), it will not break the existing data.
Zhou Shuaifeng(Frank) -----Original Message----- From: Frédéric Fondement [mailto:[email protected]] Sent: Monday, July 11, 2011 5:05 PM To: [email protected] Subject: Change compressor on existing tables Another related question: is there a mean to change compressor (or enable compressor) on an existing column family without breaking existing data (e.g. from LZO to snappy) ? Le 10/07/11 10:21, Weiwei Xiong a écrit : > Now I applied the major_compact on a table with BLOOMFILTER enabled. But how > can I make sure if the row-keys have really been added into the bloomfilter? > > > I profiled the cost of<HTable>.exists(<Get>) but it seems to me BF didn't > give me speedup comparing with the execution without BLOOMFILTER enabled. > > Am I missing anything here? > > Thanks > ww > > On Sat, Jul 9, 2011 at 1:32 PM, Weiwei Xiong<[email protected]> wrote: > >> Thanks Andrew. I will give it a try. >> >> ww >> >> >> On Fri, Jul 8, 2011 at 6:45 PM, Andrew Purtell<[email protected]>wrote: >> >>> Sorry that is: >>> >>> major_compact 'tablename' >>> >>> Typing too fast... >>> >>> Best regards, >>> >>> >>> - Andy >>> >>> Problems worthy of attack prove their worth by hitting back. - Piet Hein >>> (via Tom White) >>> >>> >>> ----- Original Message ----- >>>> From: Andrew Purtell<[email protected]> >>>> To: "[email protected]"<[email protected]> >>>> Cc: >>>> Sent: Friday, July 8, 2011 6:42 PM >>>> Subject: Re: Enable BLOOMFILTER on existing tables >>>> >>>> You can update existing data through manually triggering compaction. >>> After you >>>> make a change like this, go to the hbase shell and execute: >>>> >>>> major_compaction 'yourtablename' >>>> >>>> After major compaction all of the store files for the table will abide >>> the most >>>> recent schema settings. >>>> >>>> Best regards, >>>> >>>> >>>> - Andy >>>> >>>> >>>> Problems worthy of attack prove their worth by hitting back. - Piet Hein >>> (via >>>> Tom White) >>>> >>>> >>>> ----- Original Message ----- >>>>> From: Weiwei Xiong<[email protected]> >>>>> To: [email protected] >>>>> Cc: >>>>> Sent: Friday, July 8, 2011 6:02 PM >>>>> Subject: Enable BLOOMFILTER on existing tables >>>>> >>>>> Hi all, >>>>> >>>>> I want to enable the bloomfilter on some existing tables to speed-up >>>> row-key >>>>> existence checking. I altered the BLOOMFILTER from "NONE" to >>>>> "ROW" for this >>>>> purpose. >>>>> >>>>> But one think I am not clear is, will the setting change also take >>> effect >>>> on >>>>> pre-existing rows? Or only rows to be inserted in future get the >>>> BLOOMFILTER >>>>> property? >>>>> >>>>> If bloomfilter change won't be applied to existing rows, is there any >>>> other >>>>> way to speed up the row-key existence checking? >>>>> >>>>> Thanks, >>>>> ww >>>>> >>
