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diff --git a/src/main/java/parallelai/spyglass/jdbc/db/DBWritable.java b/src/main/java/parallelai/spyglass/jdbc/db/DBWritable.java
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+/*
+ * Copyright (c) 2009 Concurrent, Inc.
+ *
+ * This work has been released into the public domain
+ * by the copyright holder. This applies worldwide.
+ *
+ * In case this is not legally possible:
+ * The copyright holder grants any entity the right
+ * to use this work for any purpose, without any
+ * conditions, unless such conditions are required by law.
+ */
+
+package parallelai.spyglass.jdbc.db;
+
+import org.apache.hadoop.io.Writable;
+
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+/**
+ * Objects that are read from/written to a database should implement <code>DBWritable</code>.
+ * DBWritable, is similar to {@link Writable} except that the {@link #write(PreparedStatement)}
+ * method takes a {@link PreparedStatement}, and {@link #readFields(ResultSet)} takes a {@link
+ * ResultSet}. <p> Implementations are responsible for writing the fields of the object to
+ * PreparedStatement, and reading the fields of the object from the ResultSet. <p/> <p>Example:</p>
+ * If we have the following table in the database :
+ * <pre>
+ * CREATE TABLE MyTable (
+ *   counter        INTEGER NOT NULL,
+ *   timestamp      BIGINT  NOT NULL,
+ * );
+ * </pre>
+ * then we can read/write the tuples from/to the table with :
+ * <p><pre>
+ * public class MyWritable implements Writable, DBWritable {
+ *   // Some data
+ *   private int counter;
+ *   private long timestamp;
+ * <p/>
+ *   //Writable#write() implementation
+ *   public void write(DataOutput out) throws IOException {
+ *     out.writeInt(counter);
+ *     out.writeLong(timestamp);
+ *   }
+ * <p/>
+ *   //Writable#readFields() implementation
+ *   public void readFields(DataInput in) throws IOException {
+ *     counter = in.readInt();
+ *     timestamp = in.readLong();
+ *   }
+ * <p/>
+ *   public void write(PreparedStatement statement) throws SQLException {
+ *     statement.setInt(1, counter);
+ *     statement.setLong(2, timestamp);
+ *   }
+ * <p/>
+ *   public void readFields(ResultSet resultSet) throws SQLException {
+ *     counter = resultSet.getInt(1);
+ *     timestamp = resultSet.getLong(2);
+ *   }
+ * }
+ * </pre></p>
+ */
+public interface DBWritable {
+
+    /**
+     * Sets the fields of the object in the {@link PreparedStatement}.
+     *
+     * @param statement the statement that the fields are put into.
+     * @throws SQLException
+     */
+    public void write(PreparedStatement statement) throws SQLException;
+
+    /**
+     * Reads the fields of the object from the {@link ResultSet}.
+     *
+     * @param resultSet the {@link ResultSet} to get the fields from.
+     * @throws SQLException
+     */
+    public void readFields(ResultSet resultSet) throws SQLException;
+
+}