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From Apache Wiki <wikidi...@apache.org>
Subject [Lucene-hadoop Wiki] Trivial Update of "Hbase/ShellPlans" by stack
Date Wed, 08 Aug 2007 20:17:00 GMT
Dear Wiki user,

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The following page has been changed by stack:

The comment on the change is:
Added some introductory text.   Added a couple of comments.

  = Hbase Shell Plan Draft =
+ Plan is to significantly expand the set of shell operators.  Basic data manipulation and
data definition operators will be extended and evolved to be more SQL-like ([:Hbase/HbaseShell/HQL
HQL]).  More sophisticated manipulations to do relational and linear algebra, matrix additions,
multiplications, etc., will be added to a HBase subshell to keep the two operator types --
SQL-like vs. non-SQL -- distinct.
+ This project is currently in the planning stage.  [https://issues.apache.org/jira/browse/HADOOP-1608
HADOOP-1608] to add "Relational Algrebra Operators" is currently in process.
  == People Involved ==
   * '''Syntax definition.'''
    * [:udanax:Edward Yoon], Master.[[BR]]Open Collaboration, NHN corp.
    * Inchul Song, Ph.D. Candidate[[BR]]Database Lab[[BR]]Division of Computer Science, KAIST
  If you have constructive ideas, please advise me. webmaster@udanax.org
+ ''~-This page looks great. I've added comments to the below.  Please remove after you are
done with them. -- St.Ack-~''
  == Suggested Hbase Shell plans ==
  === Hbase Query Language ===
@@ -44, +50 @@

   * A Simplified processing of a logical data model
   * A Simplified algebraic operations
   * A Simplified Parallel Numerical Analysis by abstracting/numericalizing points, lines,
or plane data across multiple maps in HBase.
+  ''~-Does the import/export above include being able to write HQL/altool scripts feeding
them to the interpreter on stdin or passing the interpreter a file of script? It would be
sweet too if the interpreter could be invoked with a flag which stated how results were to
be output.  ACSII tables could be the default as it is now but users will likely want output
without formatting or output formatted as XML, etc.  Something to think about.  Also, Edward,
I'd suggest that you would be doing yourself a service if you added citations for concepts
like 'Parallel Numerical Analysis'.  It will help folks like myself does not know what this
means.  Thanks. -- St.Ack -~''
  === HBase altools Background ===
  I expect Hadoop + Hbase to handle sparsity and data explosion very well in near future.
Moreover, i believe the design of the multi-dimensional map structure and the 3d space model
of the data are optimized for rapid ad-hoc information retrieval in any orientation, as well
as for fast, flexible calculation and transformation of raw data based on formulaic relationships.
It is advantageous with respect to '''Analysis Processing'''  as it allows users to easily
formulate complex queries, and filter or slice data into meaningful subsets, among other things.
@@ -63, +71 @@

  If we decide to cut the data model in time version, then we may view the new data as a 2D
table. If index is in string, we may view it as a huge map. If index is in integer, then it
is one huge 2D array. So each table may have such data storages in 3D (Columnfamilies) Locality
Group(Columnfamilies) is a relationship that can occur between multiple references whenever
one reference brings in much of the data used by the other references.
+ ''~-I think people may also start to ask as your operators evolve: 'What is the difference
between HBase Shell and Yahoo! PIG?' -- St.Ack-~''
  === Suggested Hbase altools Syntax ===
@@ -74, +84 @@

  ||Matrix ||<99%>'''Matrix''' command constructs the configuration of the logic matrix.
[[BR]][[BR]]~-''M = Matrix(table_name, columnfamily_name[, scalar S]);''-~ ||
  ||Substitute ||<99%>'''Substitute''' expression to [A~Z][[BR]][[BR]]~-''A = Table('movieLog_table');''-~
  ||Store ||<99%>'''Store''' command will store results to specified table. [[BR]][[BR]]~-''A
= Table('movieLog_table'); [[BR]]B = A.Selection(length > 100); [[BR]]Store B TO table('tmp_table')[or
file('backup.dat')];''-~ ||
+ ''~-Do you intend to allow multi-character variables?  I think you should if possible. --
  ==== Relational Operators ====
  ||<bgcolor="#E5E5E5">'''Operator''' ||<bgcolor="#E5E5E5">'''Explanation''' ||
  ||Projection ||<99%>'''Projection''' of a relation ~+R+~, It makes a new relation
as the set that is obtained when all tuples(rows) in ~+R+~ are restricted to the set {columnfamily,,1,,,...,columnfamily,,n,,}.[[BR]][[BR]]~-''A
= Table('movieLog_table');[[BR]]B = A.Projection('year','length');''-~ ||
  ||Selection ||<99%>'''Selection''' of a relation ~+R+~, It makes a new relation as
the set of specified tuples(rows) of the relation ~+R+~[[BR]]'''Set Operations''' : ~-''OR,
AND, NOT''-~[[BR]][[BR]]~-''A = Table('movieLog_table');[[BR]]B = A.Selection(length >
100 AND studioName = 'Fox');''-~ ||
  ||Group ||<99%>'''Group''' tuples by value of an attribute and apply aggregate function
independently to each group of tuples.[[BR]]'''Aggregate Functions''' : ~-''AVG( attribute
), SUM( attribute ), COUNT( attribute ), MIN( attribute ), MAX( attribute )''-~[[BR]][[BR]]~-''A
= Table('movieLog_table);[[BR]]B = A.Group('studioName', MIN('year'));''-~ ||
  ||Sort ||<99%>'''Sort''' of tuples(rows) of R, ordered according to columnfamilies
on columnfamily-list[[BR]][[BR]]~-''A = Table('movieLog_table');[[BR]]B = Sort A by ('length');''-~
+ ''~-Again, to help readers, you might cite pages that explain 'relational algebra' or examples
of its use in databases to help contextualize your plan (Aren't there other relational operators
than these that might be included?   Do you intend to implement those?  If not, you might
say why not of if you intend to do these as 'Matrix Arithmetic Operators, you might say so.
-- St.Ack-~''
  ==== Matrix Arithmetic Operators ====
  ||<bgcolor="#E5E5E5">'''Operator''' ||<bgcolor="#E5E5E5">'''Explanation''' ||
@@ -100, +115 @@

  ||SVD ||<99%>'''SV(Singular Value) Decomposition'''[[BR]]For an m-by-n matrix A with
m >= n, the singular value decomposition is an m-by-n orthogonal matrix U, an n-by-n diagonal
matrix S, and an n-by-n orthogonal matrix V so that A = U*S*V'.[[BR]]'''Functions''' : ~-''getS(),
getU(), getV(), getSingularValues()''-~ [[BR]][[BR]]~-''A = Matrix('m_table','cf_1');[[BR]]B
= SVDecomposition(A);[[BR]]C = getU(B);''-~||
  = Implementation =
+ ''~-I'd suggest you add a section on the framework you intend to use developing operators
(Will you be using javacc to parse the shell inputs?  Will some operators run mapreduce jobs?
 Will output always be ASCII or will it specifiable?). -- St.Ack-~''
  '''Note''' : ''We should first test on local machines. -- udanax''
  [[BR]] ''Code Style Formatter'' [attachment:uncle-jim-code-style.xml]

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