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Posted to commits@pig.apache.org by ol...@apache.org on 2009/10/22 18:14:48 UTC
svn commit: r828769 - in /hadoop/pig/branches/branch-0.5: CHANGES.txt
src/docs/src/documentation/content/xdocs/piglatin_reference.xml
src/docs/src/documentation/content/xdocs/tabs.xml
src/docs/src/documentation/content/xdocs/tutorial.xml
Author: olga
Date: Thu Oct 22 16:14:47 2009
New Revision: 828769
URL: http://svn.apache.org/viewvc?rev=828769&view=rev
Log:
PIG-1039: documentation update (chandec via olgan)
Modified:
hadoop/pig/branches/branch-0.5/CHANGES.txt
hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/piglatin_reference.xml
hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tabs.xml
hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tutorial.xml
Modified: hadoop/pig/branches/branch-0.5/CHANGES.txt
URL: http://svn.apache.org/viewvc/hadoop/pig/branches/branch-0.5/CHANGES.txt?rev=828769&r1=828768&r2=828769&view=diff
==============================================================================
--- hadoop/pig/branches/branch-0.5/CHANGES.txt (original)
+++ hadoop/pig/branches/branch-0.5/CHANGES.txt Thu Oct 22 16:14:47 2009
@@ -24,6 +24,7 @@
IMPROVEMENTS
PIG-1020: Include an ant target to build pig.jar without hadoop libraries (daijy)
+PIG-1039: documentation update (chandec via olgan)
OPTIMIZATIONS
Modified: hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/piglatin_reference.xml
URL: http://svn.apache.org/viewvc/hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/piglatin_reference.xml?rev=828769&r1=828768&r2=828769&view=diff
==============================================================================
--- hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/piglatin_reference.xml (original)
+++ hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/piglatin_reference.xml Thu Oct 22 16:14:47 2009
@@ -2129,6 +2129,7 @@
<para>(condition ? value_if_true : value_if_false) </para>
<para>The bincond should be enclosed in parenthesis. </para>
<para>The schemas for the two conditional outputs of the bincond should match.</para>
+ <para>Use expressions only (relational operators are not allowed).</para>
</entry>
</row></tbody></tgroup>
</informaltable>
@@ -4750,9 +4751,9 @@
<section>
<title>Relational Operators</title>
-<section>
+ <section id="COGROUP">
<title>COGROUP</title>
- <para>COGROUP is the same as GROUP, but for readability purposes programmers usually use GROUP when only one relation is involved and COGROUP with multiple relations. See <xref linkend="GROUP" /> for more information.</para>
+ <para>COGROUP is the same as GROUP. For readability, programmers usually use GROUP when only one relation is involved and COGROUP with multiple relations re involved. See <xref linkend="GROUP" /> for more information.</para>
</section>
<section>
<title>CROSS</title>
@@ -5403,7 +5404,8 @@
<section id="GROUP">
<title>GROUP</title>
- <para>Groups the data in a one or multiple relations. For readability COGROUP is usually used with multiple relations and group is used with a single relation, but they are the same operator.</para>
+ <para>Groups the data in one or multiple relations. GROUP is the same as <xref linkend="COGROUP" />. For
+readability, programmers usually use GROUP when only one relation is involved and COGROUP with multiple relations are involved. </para>
<section>
<title>Syntax</title>
@@ -7674,7 +7676,7 @@
</row></tbody></tgroup>
</informaltable></section></section>
- <section>
+ <section >
<title>COUNT</title>
<para>Computes the number of elements in a bag. </para>
<section>
@@ -7682,7 +7684,7 @@
<informaltable frame="all">
<tgroup cols="1"><tbody><row>
<entry>
- <para>COUNT(expression)Â Â Â Â </para>
+ <para>COUNT(expression) </para>
</entry>
</row></tbody></tgroup>
</informaltable></section>
@@ -7702,11 +7704,11 @@
<section>
<title>Usage</title>
- <para>Use the COUNT function to compute the number of elements in a bag.
+ <para>Use the COUNT function to compute the number of elements in a bag.
COUNT requires a preceding GROUP ALL statement for global counts and a GROUP BY statement for group counts.</para>
<para>
- The COUNT function now ignores NULL values. If you want to include NULL values in the count computation, see
+ The COUNT function ignores NULL values. If you want to include NULL values in the count computation, use
<ulink url="piglatin_reference.html#COUNT_STAR">COUNT_STAR</ulink>.
</para>
@@ -7833,7 +7835,9 @@
<title>Usage</title>
<para>Use the COUNT_STAR function to compute the number of elements in a bag.
COUNT_STAR requires a preceding GROUP ALL statement for global counts and a GROUP BY statement for group counts.</para>
- <para>COUNT_STAR includes NULL values in the count computation (unlike COUNT, which ignores NULL values).</para>
+ <para>COUNT_STAR includes NULL values in the count computation
+ (unlike <ulink url="piglatin_reference.html#COUNT">COUNT</ulink>, which ignores NULL values).
+ </para>
</section>
<section>
@@ -8180,7 +8184,7 @@
<section>
<title>SIZE</title>
- <para>Computes the number of elements based on the data type.</para>
+ <para>Computes the number of elements based on any Pig data type. </para>
<section>
<title>Syntax</title>
@@ -8207,7 +8211,9 @@
<section>
<title>Usage</title>
- <para>Use the SIZE function to compute the number of elements based on the data type (see the Types Tables below).</para></section>
+ <para>Use the SIZE function to compute the number of elements based on the data type (see the Types Tables below).
+ SIZE includes NULL values in the size computation. SIZE is not algebraic.</para>
+ </section>
<section>
<title>Example</title>
Modified: hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tabs.xml
URL: http://svn.apache.org/viewvc/hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tabs.xml?rev=828769&r1=828768&r2=828769&view=diff
==============================================================================
--- hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tabs.xml (original)
+++ hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tabs.xml Thu Oct 22 16:14:47 2009
@@ -32,6 +32,6 @@
-->
<tab label="Project" href="http://hadoop.apache.org/pig/" type="visible" />
<tab label="Wiki" href="http://wiki.apache.org/pig/" type="visible" />
- <tab label="Pig 0.4.0 Documentation" dir="" type="visible" />
+ <tab label="Pig 0.5.0 Documentation" dir="" type="visible" />
</tabs>
Modified: hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tutorial.xml
URL: http://svn.apache.org/viewvc/hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tutorial.xml?rev=828769&r1=828768&r2=828769&view=diff
==============================================================================
--- hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tutorial.xml (original)
+++ hadoop/pig/branches/branch-0.5/src/docs/src/documentation/content/xdocs/tutorial.xml Thu Oct 22 16:14:47 2009
@@ -27,16 +27,16 @@
<section>
<title>Overview</title>
-<p>The Pig tutorial shows you how to run two Pig scripts in local mode and hadoop mode. </p>
+<p>The Pig tutorial shows you how to run two Pig scripts in local mode and mapreduce mode. </p>
<ul>
<li><p> <strong>Local Mode</strong>: To run the scripts in local mode, no Hadoop or HDFS installation is required. All files are installed and run from your local host and file system. </p>
</li>
-<li><p> <strong>Hadoop Mode</strong>: To run the scripts in hadoop (mapreduce) mode, you need access to a Hadoop cluster and HDFS installation. </p>
+<li><p> <strong>Mapreduce Mode</strong>: To run the scripts in mapreduce mode, you need access to a Hadoop cluster and HDFS installation. </p>
</li>
</ul>
<p>The Pig tutorial file (tutorial/pigtutorial.tar.gz file in the pig distribution) includes the Pig JAR file (pig.jar) and the tutorial files (tutorial.jar, Pigs scripts, log files).
-These files work with Hadoop 0.18 and provide everything you need to run the Pig scripts.</p>
+These files work with Hadoop 0.20 and provide everything you need to run the Pig scripts.</p>
<p>To get started, follow these basic steps: </p>
<ol>
@@ -119,9 +119,9 @@
</section>
<section>
-<title> Running the Pig Scripts in Hadoop Mode</title>
+<title> Running the Pig Scripts in Mapreduce Mode</title>
-<p>To run the Pig scripts in hadoop (mapreduce) mode, do the following: </p>
+<p>To run the Pig scripts in mapreduce mode, do the following: </p>
<ol>
<li><p>Move to the pigtmp directory. </p>
</li>
@@ -135,14 +135,14 @@
$ hadoop fs âcopyFromLocal excite.log.bz2 .
</source>
<ol>
-<li><p>Set the HADOOPSITEPATH environment variable to the location of your hadoop-site.xml file. </p>
+<li><p>Set the HADOOP_CONF_DIR environment variable to the location of your core-site.xml, hdfs-site.xml and mapred-site.xml files. </p>
</li>
<li><p>Execute the following command (using either script1-hadoop.pig or script2-hadoop.pig): </p>
</li>
</ol>
<source>
-$ java -cp $PIGDIR/pig.jar:$HADOOPSITEPATH org.apache.pig.Main script1-hadoop.pig
+$ java -cp $PIGDIR/pig.jar:$HADOOP_CONF_DIR org.apache.pig.Main script1-hadoop.pig
</source>
<ol>
<li><p>Review the result files (located in either the script1-hadoop-results or script2-hadoop-results HDFS directory): </p>