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Posted to common-user@hadoop.apache.org by Sai Sai <sa...@yahoo.in> on 2013/03/28 06:13:29 UTC

Re: Serialized comparator vs normal comparator


Just wondering what is the difference between serialized comparator vs normal comparator given below,
the reason i am trying to understand this is how will you verify if you r using serialized comparator during debugging if the comparator is 
working or not as when you debug in eclipse it shows byte info which cannot be understood by developers.

Here r the methods i am referring to:

/** A Comparator that compares serialized IntPair. */ 
    public static class Comparator extends WritableComparator {
      public Comparator() {
        super(IntPair.class);
      }

     public int compare(byte[] b1, int s1, int l1,
                         byte[] b2, int s2, int l2) {
        return compareBytes(b1, s1, l1, b2, s2, l2);
      }
    }

    static {                                        // register this comparator
      WritableComparator.define(IntPair.class, new Comparator());
    }

    @Override
   public int compareTo(IntPair o) {
      if (first != o.first) {
        return first < o.first ? -1 : 1;
      } else if (second != o.second) {
        return second < o.second ? -1 : 1;
      } else {
        return 0;
      }
    }

Re: Bloom Filter analogy in SQL

Posted by Ted <r6...@gmail.com>.
believe it or not, wikipedia has an excellent description of bloomfilters

http://en.wikipedia.org/wiki/Bloom_filter

On 4/16/13, Anupam Singh <av...@gmail.com> wrote:
> Many join implementations use bloom filters built on the smaller to
> eliminate rows on the larger tables in SQL queries. Many industrial RDBMS
> engines will show the use of bloom filters in SQL explain plans.
>
>
> For instance, oracle explain plans call these joins bloom filters as
> SYS_OP_BLOOM_FILTER :-
>
>
> https://forums.oracle.com/forums/thread.jspa?threadID=2470938
>
>
> It could be useful for performance tuning. Hope this helps.
>
>
> -Anupam
>
> —
> Sent from Mailbox for iPhone
>
> On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
> wrote:
>
>> This isn't a very Hadoop question.
>> A Bloom filter is a very low level data structure that doesn't really any
>> correlate in SQL.  It allows you to find duplicates quickly and
>> probabilistically.  In return for a small probability of a false
>> positive,
>> it uses less memory.
>> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>>> Can some one give a simple analogy of Bloom Filter in SQL.
>>> I am trying to understand and always get confused.
>>> Thanks
>>>


-- 
Ted.

Re: Bloom Filter analogy in SQL

Posted by Ted <r6...@gmail.com>.
believe it or not, wikipedia has an excellent description of bloomfilters

http://en.wikipedia.org/wiki/Bloom_filter

On 4/16/13, Anupam Singh <av...@gmail.com> wrote:
> Many join implementations use bloom filters built on the smaller to
> eliminate rows on the larger tables in SQL queries. Many industrial RDBMS
> engines will show the use of bloom filters in SQL explain plans.
>
>
> For instance, oracle explain plans call these joins bloom filters as
> SYS_OP_BLOOM_FILTER :-
>
>
> https://forums.oracle.com/forums/thread.jspa?threadID=2470938
>
>
> It could be useful for performance tuning. Hope this helps.
>
>
> -Anupam
>
> —
> Sent from Mailbox for iPhone
>
> On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
> wrote:
>
>> This isn't a very Hadoop question.
>> A Bloom filter is a very low level data structure that doesn't really any
>> correlate in SQL.  It allows you to find duplicates quickly and
>> probabilistically.  In return for a small probability of a false
>> positive,
>> it uses less memory.
>> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>>> Can some one give a simple analogy of Bloom Filter in SQL.
>>> I am trying to understand and always get confused.
>>> Thanks
>>>


-- 
Ted.

Re: Bloom Filter analogy in SQL

Posted by Ted <r6...@gmail.com>.
believe it or not, wikipedia has an excellent description of bloomfilters

http://en.wikipedia.org/wiki/Bloom_filter

On 4/16/13, Anupam Singh <av...@gmail.com> wrote:
> Many join implementations use bloom filters built on the smaller to
> eliminate rows on the larger tables in SQL queries. Many industrial RDBMS
> engines will show the use of bloom filters in SQL explain plans.
>
>
> For instance, oracle explain plans call these joins bloom filters as
> SYS_OP_BLOOM_FILTER :-
>
>
> https://forums.oracle.com/forums/thread.jspa?threadID=2470938
>
>
> It could be useful for performance tuning. Hope this helps.
>
>
> -Anupam
>
> —
> Sent from Mailbox for iPhone
>
> On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
> wrote:
>
>> This isn't a very Hadoop question.
>> A Bloom filter is a very low level data structure that doesn't really any
>> correlate in SQL.  It allows you to find duplicates quickly and
>> probabilistically.  In return for a small probability of a false
>> positive,
>> it uses less memory.
>> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>>> Can some one give a simple analogy of Bloom Filter in SQL.
>>> I am trying to understand and always get confused.
>>> Thanks
>>>


-- 
Ted.

Re: Bloom Filter analogy in SQL

Posted by Ted <r6...@gmail.com>.
believe it or not, wikipedia has an excellent description of bloomfilters

http://en.wikipedia.org/wiki/Bloom_filter

On 4/16/13, Anupam Singh <av...@gmail.com> wrote:
> Many join implementations use bloom filters built on the smaller to
> eliminate rows on the larger tables in SQL queries. Many industrial RDBMS
> engines will show the use of bloom filters in SQL explain plans.
>
>
> For instance, oracle explain plans call these joins bloom filters as
> SYS_OP_BLOOM_FILTER :-
>
>
> https://forums.oracle.com/forums/thread.jspa?threadID=2470938
>
>
> It could be useful for performance tuning. Hope this helps.
>
>
> -Anupam
>
> —
> Sent from Mailbox for iPhone
>
> On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
> wrote:
>
>> This isn't a very Hadoop question.
>> A Bloom filter is a very low level data structure that doesn't really any
>> correlate in SQL.  It allows you to find duplicates quickly and
>> probabilistically.  In return for a small probability of a false
>> positive,
>> it uses less memory.
>> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>>> Can some one give a simple analogy of Bloom Filter in SQL.
>>> I am trying to understand and always get confused.
>>> Thanks
>>>


-- 
Ted.

Re: Bloom Filter analogy in SQL

Posted by Anupam Singh <av...@gmail.com>.
Many join implementations use bloom filters built on the smaller to eliminate rows on the larger tables in SQL queries. Many industrial RDBMS engines will show the use of bloom filters in SQL explain plans.


For instance, oracle explain plans call these joins bloom filters as SYS_OP_BLOOM_FILTER :-


https://forums.oracle.com/forums/thread.jspa?threadID=2470938


It could be useful for performance tuning. Hope this helps.


-Anupam

—
Sent from Mailbox for iPhone

On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
wrote:

> This isn't a very Hadoop question.
> A Bloom filter is a very low level data structure that doesn't really any
> correlate in SQL.  It allows you to find duplicates quickly and
> probabilistically.  In return for a small probability of a false positive,
> it uses less memory.
> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>> Can some one give a simple analogy of Bloom Filter in SQL.
>> I am trying to understand and always get confused.
>> Thanks
>>

Re: Bloom Filter analogy in SQL

Posted by Anupam Singh <av...@gmail.com>.
Many join implementations use bloom filters built on the smaller to eliminate rows on the larger tables in SQL queries. Many industrial RDBMS engines will show the use of bloom filters in SQL explain plans.


For instance, oracle explain plans call these joins bloom filters as SYS_OP_BLOOM_FILTER :-


https://forums.oracle.com/forums/thread.jspa?threadID=2470938


It could be useful for performance tuning. Hope this helps.


-Anupam

—
Sent from Mailbox for iPhone

On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
wrote:

> This isn't a very Hadoop question.
> A Bloom filter is a very low level data structure that doesn't really any
> correlate in SQL.  It allows you to find duplicates quickly and
> probabilistically.  In return for a small probability of a false positive,
> it uses less memory.
> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>> Can some one give a simple analogy of Bloom Filter in SQL.
>> I am trying to understand and always get confused.
>> Thanks
>>

Re: Bloom Filter analogy in SQL

Posted by Anupam Singh <av...@gmail.com>.
Many join implementations use bloom filters built on the smaller to eliminate rows on the larger tables in SQL queries. Many industrial RDBMS engines will show the use of bloom filters in SQL explain plans.


For instance, oracle explain plans call these joins bloom filters as SYS_OP_BLOOM_FILTER :-


https://forums.oracle.com/forums/thread.jspa?threadID=2470938


It could be useful for performance tuning. Hope this helps.


-Anupam

—
Sent from Mailbox for iPhone

On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
wrote:

> This isn't a very Hadoop question.
> A Bloom filter is a very low level data structure that doesn't really any
> correlate in SQL.  It allows you to find duplicates quickly and
> probabilistically.  In return for a small probability of a false positive,
> it uses less memory.
> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>> Can some one give a simple analogy of Bloom Filter in SQL.
>> I am trying to understand and always get confused.
>> Thanks
>>

Re: Bloom Filter analogy in SQL

Posted by Anupam Singh <av...@gmail.com>.
Many join implementations use bloom filters built on the smaller to eliminate rows on the larger tables in SQL queries. Many industrial RDBMS engines will show the use of bloom filters in SQL explain plans.


For instance, oracle explain plans call these joins bloom filters as SYS_OP_BLOOM_FILTER :-


https://forums.oracle.com/forums/thread.jspa?threadID=2470938


It could be useful for performance tuning. Hope this helps.


-Anupam

—
Sent from Mailbox for iPhone

On Fri, Mar 29, 2013 at 11:32 PM, Ted Dunning <td...@maprtech.com>
wrote:

> This isn't a very Hadoop question.
> A Bloom filter is a very low level data structure that doesn't really any
> correlate in SQL.  It allows you to find duplicates quickly and
> probabilistically.  In return for a small probability of a false positive,
> it uses less memory.
> On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:
>> Can some one give a simple analogy of Bloom Filter in SQL.
>> I am trying to understand and always get confused.
>> Thanks
>>

Re: Bloom Filter analogy in SQL

Posted by Ted Dunning <td...@maprtech.com>.
This isn't a very Hadoop question.

A Bloom filter is a very low level data structure that doesn't really any
correlate in SQL.  It allows you to find duplicates quickly and
probabilistically.  In return for a small probability of a false positive,
it uses less memory.


On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

Re: Bloom Filter analogy in SQL

Posted by Ted Dunning <td...@maprtech.com>.
This isn't a very Hadoop question.

A Bloom filter is a very low level data structure that doesn't really any
correlate in SQL.  It allows you to find duplicates quickly and
probabilistically.  In return for a small probability of a false positive,
it uses less memory.


On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

Re: Bloom Filter analogy in SQL

Posted by Kai Voigt <k...@123.org>.
http://billmill.org/bloomfilter-tutorial/ has nice explanation, and it links to the Wiki entry for further theory.


Am 07.05.2013 um 16:56 schrieb Tony Burton <TB...@SportingIndex.com>:

> There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.
>  
>  
> From: Sai Sai [mailto:saigraph@yahoo.in] 
> Sent: 29 March 2013 16:37
> To: user@hadoop.apache.org
> Subject: Re: Bloom Filter analogy in SQL
>  
> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>  
> 
> 
> *****************************************************************************
> P Pleaseconsider the environment before printing this email
> 
> 
> Inbound email has been scanned for viruses & spam
> 
> 
> 
> 
> *****************************************************************************
> P Please consider the environment before printing this email or attachments
> 
> 
> This email and any attachments are confidential, protected by copyright and may be legally privileged. If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system. Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened. It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email. Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP. Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001). Any financial promotion contained herein has been issued and approved by Sporting Index Ltd.
> 
> 
> Outbound email has been scanned for viruses and SPAM
> 

-- 
Kai Voigt
k@123.org





Re: Bloom Filter analogy in SQL

Posted by Kai Voigt <k...@123.org>.
http://billmill.org/bloomfilter-tutorial/ has nice explanation, and it links to the Wiki entry for further theory.


Am 07.05.2013 um 16:56 schrieb Tony Burton <TB...@SportingIndex.com>:

> There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.
>  
>  
> From: Sai Sai [mailto:saigraph@yahoo.in] 
> Sent: 29 March 2013 16:37
> To: user@hadoop.apache.org
> Subject: Re: Bloom Filter analogy in SQL
>  
> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>  
> 
> 
> *****************************************************************************
> P Pleaseconsider the environment before printing this email
> 
> 
> Inbound email has been scanned for viruses & spam
> 
> 
> 
> 
> *****************************************************************************
> P Please consider the environment before printing this email or attachments
> 
> 
> This email and any attachments are confidential, protected by copyright and may be legally privileged. If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system. Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened. It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email. Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP. Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001). Any financial promotion contained herein has been issued and approved by Sporting Index Ltd.
> 
> 
> Outbound email has been scanned for viruses and SPAM
> 

-- 
Kai Voigt
k@123.org





Re: Bloom Filter analogy in SQL

Posted by Kai Voigt <k...@123.org>.
http://billmill.org/bloomfilter-tutorial/ has nice explanation, and it links to the Wiki entry for further theory.


Am 07.05.2013 um 16:56 schrieb Tony Burton <TB...@SportingIndex.com>:

> There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.
>  
>  
> From: Sai Sai [mailto:saigraph@yahoo.in] 
> Sent: 29 March 2013 16:37
> To: user@hadoop.apache.org
> Subject: Re: Bloom Filter analogy in SQL
>  
> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>  
> 
> 
> *****************************************************************************
> P Pleaseconsider the environment before printing this email
> 
> 
> Inbound email has been scanned for viruses & spam
> 
> 
> 
> 
> *****************************************************************************
> P Please consider the environment before printing this email or attachments
> 
> 
> This email and any attachments are confidential, protected by copyright and may be legally privileged. If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system. Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened. It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email. Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP. Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001). Any financial promotion contained herein has been issued and approved by Sporting Index Ltd.
> 
> 
> Outbound email has been scanned for viruses and SPAM
> 

-- 
Kai Voigt
k@123.org





Re: Bloom Filter analogy in SQL

Posted by Kai Voigt <k...@123.org>.
http://billmill.org/bloomfilter-tutorial/ has nice explanation, and it links to the Wiki entry for further theory.


Am 07.05.2013 um 16:56 schrieb Tony Burton <TB...@SportingIndex.com>:

> There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.
>  
>  
> From: Sai Sai [mailto:saigraph@yahoo.in] 
> Sent: 29 March 2013 16:37
> To: user@hadoop.apache.org
> Subject: Re: Bloom Filter analogy in SQL
>  
> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>  
> 
> 
> *****************************************************************************
> P Pleaseconsider the environment before printing this email
> 
> 
> Inbound email has been scanned for viruses & spam
> 
> 
> 
> 
> *****************************************************************************
> P Please consider the environment before printing this email or attachments
> 
> 
> This email and any attachments are confidential, protected by copyright and may be legally privileged. If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system. Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened. It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email. Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP. Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001). Any financial promotion contained herein has been issued and approved by Sporting Index Ltd.
> 
> 
> Outbound email has been scanned for viruses and SPAM
> 

-- 
Kai Voigt
k@123.org





RE: Bloom Filter analogy in SQL

Posted by Tony Burton <TB...@SportingIndex.com>.
There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.


From: Sai Sai [mailto:saigraph@yahoo.in]
Sent: 29 March 2013 16:37
To: user@hadoop.apache.org
Subject: Re: Bloom Filter analogy in SQL

Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks


*****************************************************************************
P Pleaseconsider the environment before printing this email

Inbound email has been scanned for viruses & spam

**********************************************************************
Please consider the environment before printing this email or attachments

This email and any attachments are confidential, protected by copyright and may be legally privileged.  If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system.  Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened.  It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email.  Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP.  Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001).  Any financial promotion contained herein has been issued
and approved by Sporting Index Ltd.

Outbound email has been scanned for viruses and SPAM

Re: list of linux commands for hadoop

Posted by Sai Sai <sa...@yahoo.in>.
Just wondering if there are a list of linux commands or any article which r needed for learning hadoop.
Thanks

Re: list of linux commands for hadoop

Posted by Sai Sai <sa...@yahoo.in>.
Just wondering if there are a list of linux commands or any article which r needed for learning hadoop.
Thanks

Re: Bloom Filter analogy in SQL

Posted by Ted Yu <yu...@gmail.com>.
>From http://msdn.microsoft.com/en-us/library/cc278097(v=sql.100).aspx :

The new technology employed is based on bitmap filters, also known as *Bloom
filters *(see *Bloom filter, *Wikipedia 2007,
http://en.wikipedia.org/wiki/Bloom_filter) ...

HBase uses bloom filters extensively. I can give references if you're
interested.


On Fri, Mar 29, 2013 at 9:36 AM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

RE: Bloom Filter analogy in SQL

Posted by Tony Burton <TB...@SportingIndex.com>.
There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.


From: Sai Sai [mailto:saigraph@yahoo.in]
Sent: 29 March 2013 16:37
To: user@hadoop.apache.org
Subject: Re: Bloom Filter analogy in SQL

Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks


*****************************************************************************
P Pleaseconsider the environment before printing this email

Inbound email has been scanned for viruses & spam

**********************************************************************
Please consider the environment before printing this email or attachments

This email and any attachments are confidential, protected by copyright and may be legally privileged.  If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system.  Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened.  It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email.  Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP.  Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001).  Any financial promotion contained herein has been issued
and approved by Sporting Index Ltd.

Outbound email has been scanned for viruses and SPAM

Re: Bloom Filter analogy in SQL

Posted by Ted Yu <yu...@gmail.com>.
>From http://msdn.microsoft.com/en-us/library/cc278097(v=sql.100).aspx :

The new technology employed is based on bitmap filters, also known as *Bloom
filters *(see *Bloom filter, *Wikipedia 2007,
http://en.wikipedia.org/wiki/Bloom_filter) ...

HBase uses bloom filters extensively. I can give references if you're
interested.


On Fri, Mar 29, 2013 at 9:36 AM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

RE: Bloom Filter analogy in SQL

Posted by Tony Burton <TB...@SportingIndex.com>.
There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.


From: Sai Sai [mailto:saigraph@yahoo.in]
Sent: 29 March 2013 16:37
To: user@hadoop.apache.org
Subject: Re: Bloom Filter analogy in SQL

Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks


*****************************************************************************
P Pleaseconsider the environment before printing this email

Inbound email has been scanned for viruses & spam

**********************************************************************
Please consider the environment before printing this email or attachments

This email and any attachments are confidential, protected by copyright and may be legally privileged.  If you are not the intended recipient, then the dissemination or copying of this email is prohibited. If you have received this in error, please notify the sender by replying by email and then delete the email completely from your system.  Neither Sporting Index nor the sender accepts responsibility for any virus, or any other defect which might affect any computer or IT system into which the email is received and/or opened.  It is the responsibility of the recipient to scan the email and no responsibility is accepted for any loss or damage arising in any way from receipt or use of this email.  Sporting Index Ltd is a company registered in England and Wales with company number 2636842, whose registered office is at Gateway House, Milverton Street, London, SE11 4AP.  Sporting Index Ltd is authorised and regulated by the UK Financial Services Authority (reg. no. 150404) and Gambling Commission (reg. no. 000-027343-R-308898-001).  Any financial promotion contained herein has been issued
and approved by Sporting Index Ltd.

Outbound email has been scanned for viruses and SPAM

Re: Bloom Filter analogy in SQL

Posted by Ted Yu <yu...@gmail.com>.
>From http://msdn.microsoft.com/en-us/library/cc278097(v=sql.100).aspx :

The new technology employed is based on bitmap filters, also known as *Bloom
filters *(see *Bloom filter, *Wikipedia 2007,
http://en.wikipedia.org/wiki/Bloom_filter) ...

HBase uses bloom filters extensively. I can give references if you're
interested.


On Fri, Mar 29, 2013 at 9:36 AM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

Re: Bloom Filter analogy in SQL

Posted by Ted Dunning <td...@maprtech.com>.
This isn't a very Hadoop question.

A Bloom filter is a very low level data structure that doesn't really any
correlate in SQL.  It allows you to find duplicates quickly and
probabilistically.  In return for a small probability of a false positive,
it uses less memory.


On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

RE: Bloom Filter analogy in SQL

Posted by Tony Burton <TB...@SportingIndex.com>.
There’s an explanation of Bloom Filters and a MapReduce implementation in Chuck Lam’s book “Hadoop In Action”. Maybe that might guide the way a bit more.


From: Sai Sai [mailto:saigraph@yahoo.in]
Sent: 29 March 2013 16:37
To: user@hadoop.apache.org
Subject: Re: Bloom Filter analogy in SQL

Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks


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Re: Bloom Filter analogy in SQL

Posted by Ted Dunning <td...@maprtech.com>.
This isn't a very Hadoop question.

A Bloom filter is a very low level data structure that doesn't really any
correlate in SQL.  It allows you to find duplicates quickly and
probabilistically.  In return for a small probability of a false positive,
it uses less memory.


On Fri, Mar 29, 2013 at 5:36 PM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

Re: list of linux commands for hadoop

Posted by Sai Sai <sa...@yahoo.in>.
Just wondering if there are a list of linux commands or any article which r needed for learning hadoop.
Thanks

Re: Bloom Filter analogy in SQL

Posted by Ted Yu <yu...@gmail.com>.
>From http://msdn.microsoft.com/en-us/library/cc278097(v=sql.100).aspx :

The new technology employed is based on bitmap filters, also known as *Bloom
filters *(see *Bloom filter, *Wikipedia 2007,
http://en.wikipedia.org/wiki/Bloom_filter) ...

HBase uses bloom filters extensively. I can give references if you're
interested.


On Fri, Mar 29, 2013 at 9:36 AM, Sai Sai <sa...@yahoo.in> wrote:

> Can some one give a simple analogy of Bloom Filter in SQL.
> I am trying to understand and always get confused.
> Thanks
>

Re: list of linux commands for hadoop

Posted by Sai Sai <sa...@yahoo.in>.
Just wondering if there are a list of linux commands or any article which r needed for learning hadoop.
Thanks

Re: Bloom Filter analogy in SQL

Posted by Sai Sai <sa...@yahoo.in>.
Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks

Re: Bloom Filter analogy in SQL

Posted by Sai Sai <sa...@yahoo.in>.
Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks

Re: Bloom Filter analogy in SQL

Posted by Sai Sai <sa...@yahoo.in>.
Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks

Re: Bloom Filter analogy in SQL

Posted by Sai Sai <sa...@yahoo.in>.
Can some one give a simple analogy of Bloom Filter in SQL.
I am trying to understand and always get confused.
Thanks