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Posted to commits@cassandra.apache.org by br...@apache.org on 2012/05/26 17:50:17 UTC
[3/3] git commit: Update pig readme
Update pig readme
Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo
Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/2dc27a17
Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/2dc27a17
Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/2dc27a17
Branch: refs/heads/cassandra-1.1
Commit: 2dc27a17567fa448aae335e74cc46ab94339eba4
Parents: db68e03
Author: Brandon Williams <br...@apache.org>
Authored: Sat May 26 10:50:00 2012 -0500
Committer: Brandon Williams <br...@apache.org>
Committed: Sat May 26 10:50:00 2012 -0500
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examples/pig/README.txt | 19 +++++++++++++++++--
1 files changed, 17 insertions(+), 2 deletions(-)
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http://git-wip-us.apache.org/repos/asf/cassandra/blob/2dc27a17/examples/pig/README.txt
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diff --git a/examples/pig/README.txt b/examples/pig/README.txt
index 3bdbf10..57b8f57 100644
--- a/examples/pig/README.txt
+++ b/examples/pig/README.txt
@@ -1,7 +1,8 @@
A Pig storage class that reads all columns from a given ColumnFamily, or writes
properly formatted results into a ColumnFamily.
-Setup:
+Getting Started
+===============
First build and start a Cassandra server with the default
configuration and set the PIG_HOME and JAVA_HOME environment
@@ -31,7 +32,6 @@ for input and output:
* PIG_OUTPUT_RPC_PORT : the port thrift is listening on for writing
* PIG_OUTPUT_PARTITIONER : cluster partitioner for writing
-
Then you can run it like this:
examples/pig$ bin/pig_cassandra -x local example-script.pig
@@ -70,3 +70,18 @@ Which will copy the ColumnFamily. Note that the destination ColumnFamily must
already exist for this to work.
See the example in test/ to see how schema is inferred.
+
+Advanced Options
+================
+
+The following environment variables default to false but can be set to true to enable them:
+
+PIG_WIDEROW_INPUT: this enables loading of rows with many columns without
+ incurring memory pressure. All columns will be in a bag and indexes are not
+ supported.
+
+PIG_USE_SECONDARY: this allows easy use of secondary indexes within your
+ script, by appending every index to the schema as 'index_$name', allowing
+ filtering of loaded rows with a statement like "FILTER rows BY index_color eq
+ 'blue'" if you have an index called 'color' defined.
+