1 | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> |
---|
2 | <!--NewPage--> |
---|
3 | <HTML> |
---|
4 | <HEAD> |
---|
5 | <!-- Generated by javadoc (build 1.6.0_07) on Tue Sep 01 20:56:59 UTC 2009 --> |
---|
6 | <TITLE> |
---|
7 | org.apache.hadoop.mapred.lib.db (Hadoop 0.20.1 API) |
---|
8 | </TITLE> |
---|
9 | |
---|
10 | <META NAME="date" CONTENT="2009-09-01"> |
---|
11 | |
---|
12 | <LINK REL ="stylesheet" TYPE="text/css" HREF="../../../../../../stylesheet.css" TITLE="Style"> |
---|
13 | |
---|
14 | <SCRIPT type="text/javascript"> |
---|
15 | function windowTitle() |
---|
16 | { |
---|
17 | if (location.href.indexOf('is-external=true') == -1) { |
---|
18 | parent.document.title="org.apache.hadoop.mapred.lib.db (Hadoop 0.20.1 API)"; |
---|
19 | } |
---|
20 | } |
---|
21 | </SCRIPT> |
---|
22 | <NOSCRIPT> |
---|
23 | </NOSCRIPT> |
---|
24 | |
---|
25 | </HEAD> |
---|
26 | |
---|
27 | <BODY BGCOLOR="white" onload="windowTitle();"> |
---|
28 | <HR> |
---|
29 | |
---|
30 | |
---|
31 | <!-- ========= START OF TOP NAVBAR ======= --> |
---|
32 | <A NAME="navbar_top"><!-- --></A> |
---|
33 | <A HREF="#skip-navbar_top" title="Skip navigation links"></A> |
---|
34 | <TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY=""> |
---|
35 | <TR> |
---|
36 | <TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> |
---|
37 | <A NAME="navbar_top_firstrow"><!-- --></A> |
---|
38 | <TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY=""> |
---|
39 | <TR ALIGN="center" VALIGN="top"> |
---|
40 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD> |
---|
41 | <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Package</B></FONT> </TD> |
---|
42 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <FONT CLASS="NavBarFont1">Class</FONT> </TD> |
---|
43 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-use.html"><FONT CLASS="NavBarFont1"><B>Use</B></FONT></A> </TD> |
---|
44 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD> |
---|
45 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD> |
---|
46 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD> |
---|
47 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD> |
---|
48 | </TR> |
---|
49 | </TABLE> |
---|
50 | </TD> |
---|
51 | <TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM> |
---|
52 | </EM> |
---|
53 | </TD> |
---|
54 | </TR> |
---|
55 | |
---|
56 | <TR> |
---|
57 | <TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> |
---|
58 | <A HREF="../../../../../../org/apache/hadoop/mapred/lib/aggregate/package-summary.html"><B>PREV PACKAGE</B></A> |
---|
59 | <A HREF="../../../../../../org/apache/hadoop/mapred/pipes/package-summary.html"><B>NEXT PACKAGE</B></A></FONT></TD> |
---|
60 | <TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> |
---|
61 | <A HREF="../../../../../../index.html?org/apache/hadoop/mapred/lib/db/package-summary.html" target="_top"><B>FRAMES</B></A> |
---|
62 | <A HREF="package-summary.html" target="_top"><B>NO FRAMES</B></A> |
---|
63 | <SCRIPT type="text/javascript"> |
---|
64 | <!-- |
---|
65 | if(window==top) { |
---|
66 | document.writeln('<A HREF="../../../../../../allclasses-noframe.html"><B>All Classes</B></A>'); |
---|
67 | } |
---|
68 | //--> |
---|
69 | </SCRIPT> |
---|
70 | <NOSCRIPT> |
---|
71 | <A HREF="../../../../../../allclasses-noframe.html"><B>All Classes</B></A> |
---|
72 | </NOSCRIPT> |
---|
73 | |
---|
74 | |
---|
75 | </FONT></TD> |
---|
76 | </TR> |
---|
77 | </TABLE> |
---|
78 | <A NAME="skip-navbar_top"></A> |
---|
79 | <!-- ========= END OF TOP NAVBAR ========= --> |
---|
80 | |
---|
81 | <HR> |
---|
82 | <H2> |
---|
83 | Package org.apache.hadoop.mapred.lib.db |
---|
84 | </H2> |
---|
85 | org.apache.hadoop.mapred.lib.db Package |
---|
86 | <P> |
---|
87 | <B>See:</B> |
---|
88 | <BR> |
---|
89 | <A HREF="#package_description"><B>Description</B></A> |
---|
90 | <P> |
---|
91 | |
---|
92 | <TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY=""> |
---|
93 | <TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"> |
---|
94 | <TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2"> |
---|
95 | <B>Interface Summary</B></FONT></TH> |
---|
96 | </TR> |
---|
97 | <TR BGCOLOR="white" CLASS="TableRowColor"> |
---|
98 | <TD WIDTH="15%"><B><A HREF="../../../../../../org/apache/hadoop/mapred/lib/db/DBWritable.html" title="interface in org.apache.hadoop.mapred.lib.db">DBWritable</A></B></TD> |
---|
99 | <TD>Objects that are read from/written to a database should implement |
---|
100 | <code>DBWritable</code>.</TD> |
---|
101 | </TR> |
---|
102 | </TABLE> |
---|
103 | |
---|
104 | |
---|
105 | <P> |
---|
106 | |
---|
107 | <TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY=""> |
---|
108 | <TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"> |
---|
109 | <TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2"> |
---|
110 | <B>Class Summary</B></FONT></TH> |
---|
111 | </TR> |
---|
112 | <TR BGCOLOR="white" CLASS="TableRowColor"> |
---|
113 | <TD WIDTH="15%"><B><A HREF="../../../../../../org/apache/hadoop/mapred/lib/db/DBConfiguration.html" title="class in org.apache.hadoop.mapred.lib.db">DBConfiguration</A></B></TD> |
---|
114 | <TD>A container for configuration property names for jobs with DB input/output.</TD> |
---|
115 | </TR> |
---|
116 | <TR BGCOLOR="white" CLASS="TableRowColor"> |
---|
117 | <TD WIDTH="15%"><B><A HREF="../../../../../../org/apache/hadoop/mapred/lib/db/DBInputFormat.html" title="class in org.apache.hadoop.mapred.lib.db">DBInputFormat<T extends DBWritable></A></B></TD> |
---|
118 | <TD>A InputFormat that reads input data from an SQL table.</TD> |
---|
119 | </TR> |
---|
120 | <TR BGCOLOR="white" CLASS="TableRowColor"> |
---|
121 | <TD WIDTH="15%"><B><A HREF="../../../../../../org/apache/hadoop/mapred/lib/db/DBInputFormat.DBInputSplit.html" title="class in org.apache.hadoop.mapred.lib.db">DBInputFormat.DBInputSplit</A></B></TD> |
---|
122 | <TD>A InputSplit that spans a set of rows</TD> |
---|
123 | </TR> |
---|
124 | <TR BGCOLOR="white" CLASS="TableRowColor"> |
---|
125 | <TD WIDTH="15%"><B><A HREF="../../../../../../org/apache/hadoop/mapred/lib/db/DBInputFormat.NullDBWritable.html" title="class in org.apache.hadoop.mapred.lib.db">DBInputFormat.NullDBWritable</A></B></TD> |
---|
126 | <TD>A Class that does nothing, implementing DBWritable</TD> |
---|
127 | </TR> |
---|
128 | <TR BGCOLOR="white" CLASS="TableRowColor"> |
---|
129 | <TD WIDTH="15%"><B><A HREF="../../../../../../org/apache/hadoop/mapred/lib/db/DBOutputFormat.html" title="class in org.apache.hadoop.mapred.lib.db">DBOutputFormat<K extends DBWritable,V></A></B></TD> |
---|
130 | <TD>A OutputFormat that sends the reduce output to a SQL table.</TD> |
---|
131 | </TR> |
---|
132 | </TABLE> |
---|
133 | |
---|
134 | |
---|
135 | <P> |
---|
136 | <A NAME="package_description"><!-- --></A><H2> |
---|
137 | Package org.apache.hadoop.mapred.lib.db Description |
---|
138 | </H2> |
---|
139 | |
---|
140 | <P> |
---|
141 | <h2>org.apache.hadoop.mapred.lib.db Package</h2> |
---|
142 | <p> |
---|
143 | This package contains a library to read records from a database as an |
---|
144 | input to a mapreduce job, and write the output records to the database. |
---|
145 | </p> |
---|
146 | <p> |
---|
147 | The Database to access can be configured using the static methods in the |
---|
148 | DBConfiguration class. Jobs reading input from a database should use |
---|
149 | DBInputFormat#setInput() to set the configuration. And jobs writing |
---|
150 | its output to the database should use DBOutputFormat#setOutput(). |
---|
151 | </p> |
---|
152 | <p> |
---|
153 | Tuples from/to the database are converted to/from Java objects using |
---|
154 | DBWritable methods. Typically, for each table in the db, a class extending |
---|
155 | DBWritable is defined, which holds the fields of the tuple. The fields |
---|
156 | of a record are read from the database using DBWritable#readFields(ResultSet), |
---|
157 | and written to the database using DBWritable#write(PreparedStatament |
---|
158 | statement). |
---|
159 | </p> |
---|
160 | <p> |
---|
161 | An example program using both DBInputFormat and DBOutputFormat can be found |
---|
162 | at src/examples/org/apache/hadoop/examples/DBCountPageview.java. |
---|
163 | </p> |
---|
164 | <P> |
---|
165 | |
---|
166 | <P> |
---|
167 | <DL> |
---|
168 | </DL> |
---|
169 | <HR> |
---|
170 | |
---|
171 | |
---|
172 | <!-- ======= START OF BOTTOM NAVBAR ====== --> |
---|
173 | <A NAME="navbar_bottom"><!-- --></A> |
---|
174 | <A HREF="#skip-navbar_bottom" title="Skip navigation links"></A> |
---|
175 | <TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY=""> |
---|
176 | <TR> |
---|
177 | <TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> |
---|
178 | <A NAME="navbar_bottom_firstrow"><!-- --></A> |
---|
179 | <TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY=""> |
---|
180 | <TR ALIGN="center" VALIGN="top"> |
---|
181 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD> |
---|
182 | <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Package</B></FONT> </TD> |
---|
183 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <FONT CLASS="NavBarFont1">Class</FONT> </TD> |
---|
184 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-use.html"><FONT CLASS="NavBarFont1"><B>Use</B></FONT></A> </TD> |
---|
185 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD> |
---|
186 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD> |
---|
187 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD> |
---|
188 | <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD> |
---|
189 | </TR> |
---|
190 | </TABLE> |
---|
191 | </TD> |
---|
192 | <TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM> |
---|
193 | </EM> |
---|
194 | </TD> |
---|
195 | </TR> |
---|
196 | |
---|
197 | <TR> |
---|
198 | <TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> |
---|
199 | <A HREF="../../../../../../org/apache/hadoop/mapred/lib/aggregate/package-summary.html"><B>PREV PACKAGE</B></A> |
---|
200 | <A HREF="../../../../../../org/apache/hadoop/mapred/pipes/package-summary.html"><B>NEXT PACKAGE</B></A></FONT></TD> |
---|
201 | <TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> |
---|
202 | <A HREF="../../../../../../index.html?org/apache/hadoop/mapred/lib/db/package-summary.html" target="_top"><B>FRAMES</B></A> |
---|
203 | <A HREF="package-summary.html" target="_top"><B>NO FRAMES</B></A> |
---|
204 | <SCRIPT type="text/javascript"> |
---|
205 | <!-- |
---|
206 | if(window==top) { |
---|
207 | document.writeln('<A HREF="../../../../../../allclasses-noframe.html"><B>All Classes</B></A>'); |
---|
208 | } |
---|
209 | //--> |
---|
210 | </SCRIPT> |
---|
211 | <NOSCRIPT> |
---|
212 | <A HREF="../../../../../../allclasses-noframe.html"><B>All Classes</B></A> |
---|
213 | </NOSCRIPT> |
---|
214 | |
---|
215 | |
---|
216 | </FONT></TD> |
---|
217 | </TR> |
---|
218 | </TABLE> |
---|
219 | <A NAME="skip-navbar_bottom"></A> |
---|
220 | <!-- ======== END OF BOTTOM NAVBAR ======= --> |
---|
221 | |
---|
222 | <HR> |
---|
223 | Copyright © 2009 The Apache Software Foundation |
---|
224 | </BODY> |
---|
225 | </HTML> |
---|