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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hbase/HbaseShell/HQL" by stack
Date Sat, 09 Feb 2008 21:30:31 GMT
Dear Wiki user,

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The following page has been changed by stack:
http://wiki.apache.org/hadoop/Hbase/HbaseShell/HQL

The comment on the change is:
Comments

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    }
  }}}
  
+ ''Why not go whole way and implement the [http://java.sun.com/j2se/1.4.2/docs/api/java/sql/ResultSet.html
java.sql.ResultSet] interface, etc.?  Would it fit? St.Ack''
+ 
  == External HQL Query file ==
  HQL Query file is used for construct schema, table, and column references. It'll be created
using table dump (or manually), and can be fed into Hbase to re-create the tables. 
  
@@ -36, +38 @@

  hql > load query file 'hdfs://hbase/script.hql';
  }}}
  
+ 
+ ''A file of data definition shouldn't be called a 'query file' -- and why can't the file
just as easily load data?  Can you think of something else to call it?  And its possible to
do "$ cat DATA_DEFINITION_FILE|./bin/hbase shell" to get the same effect? St.Ack''
  == Parallel Execution Features ==
  
  === Query ===
@@ -46, +50 @@

  hql > select count(*) from tbl_name;
  hql > alter table tbl_name noparallel;
  }}}
+ 
+ ''This sets a 'parallel' property on whole table (could be just a column?)?  Whats this
do? When you do selects, does MR job?  St.Ack''
  
  === Data Loading ===
  HQL Loader utility loads data into Hbase tables from external files. If you have a large
amount of data to load, HQL Loader's parallel support can dramatically reduce the elapsed
time needed to perform that load.
@@ -58, +64 @@

    --> (column1[, column2, ...]);
  }}}
  
+ 
+ ''Why not do something like mysql where it loads and dumps a near-binary format?  Problem
w/ above is what to do if cell has tab or new-line in it?  St.Ack''
  === Data Dumping ===
  

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