PreparedBatch should clear bindings after execute()
The PreparedBatch class produces duplicate entries in the database when you invoke the execute() method multiple times. This sems to happen only when the bindBean() method is used. The attached file contains a test that illustrates the problem.

[TestPreparedBatch.java.txt](https://github.com/jdbi/jdbi/files/1642755/TestPreparedBatch.java.txt)



diff --git a/core/src/main/java/org/jdbi/v3/core/statement/PreparedBatch.java b/core/src/main/java/org/jdbi/v3/core/statement/PreparedBatch.java
index c75687074..26e517966 100644
--- a/core/src/main/java/org/jdbi/v3/core/statement/PreparedBatch.java
+++ b/core/src/main/java/org/jdbi/v3/core/statement/PreparedBatch.java
@@ -189,6 +189,8 @@ public class PreparedBatch extends SqlStatement<PreparedBatch> implements Result
 
                 afterExecution(stmt);
 
+                getContext().setBinding(new Binding());
+
                 return new ExecutedBatch(stmt, rs);
             }
             catch (SQLException e) {
diff --git a/core/src/test/java/org/jdbi/v3/core/statement/TestPreparedBatch.java b/core/src/test/java/org/jdbi/v3/core/statement/TestPreparedBatch.java
index 72ecedc9e..a16f09aec 100644
--- a/core/src/test/java/org/jdbi/v3/core/statement/TestPreparedBatch.java
+++ b/core/src/test/java/org/jdbi/v3/core/statement/TestPreparedBatch.java
@@ -16,6 +16,7 @@ package org.jdbi.v3.core.statement;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.fail;
 
+import java.beans.ConstructorProperties;
 import java.util.List;
 import java.util.Map;
 
@@ -23,6 +24,7 @@ import com.google.common.collect.ImmutableMap;
 
 import org.jdbi.v3.core.Handle;
 import org.jdbi.v3.core.Something;
+import org.jdbi.v3.core.mapper.reflect.ConstructorMapper;
 import org.jdbi.v3.core.rule.H2DatabaseRule;
 import org.junit.After;
 import org.junit.Before;
@@ -172,4 +174,79 @@ public class TestPreparedBatch
             assertThat(ctx.getBinding().findForName("name", ctx).toString()).contains("bob");
         }
     }
+
+    @Test
+    public void testMultipleExecuteBindBean()
+    {
+        final PreparedBatch b = h.prepareBatch("insert into something (id, name) values (:id, :name)");
+
+        b.bindBean(new Something(1, "Eric")).add();
+        b.bindBean(new Something(2, "Brian")).add();
+        b.execute();
+
+        // bindings should be cleared after execute()
+
+        b.bindBean(new Something(3, "Keith")).add();
+        b.execute();
+
+        final List<Something> r = h.createQuery("select * from something order by id").mapToBean(Something.class).list();
+        assertThat(r).hasSize(3);
+        assertThat(r.get(0)).extracting(Something::getId, Something::getName).containsSequence(1, "Eric");
+        assertThat(r.get(1)).extracting(Something::getId, Something::getName).containsSequence(2, "Brian");
+        assertThat(r.get(2)).extracting(Something::getId, Something::getName).containsSequence(3, "Keith");
+    }
+
+    @Test
+    public void testMultipleExecuteBind()
+    {
+        final PreparedBatch b = h.prepareBatch("insert into something (id, name) values (:id, :name)");
+
+        b.bind("id", 1).bind("name", "Eric").add();
+        b.bind("id", 2).bind("name", "Brian").add();
+        b.execute();
+
+        // bindings should be cleared after execute()
+
+        b.bind("id", 3).bind("name", "Keith").add();
+        b.execute();
+
+        final List<Something> r = h.createQuery("select * from something order by id").mapToBean(Something.class).list();
+        assertThat(r).hasSize(3);
+        assertThat(r.get(0)).extracting(Something::getId, Something::getName).containsSequence(1, "Eric");
+        assertThat(r.get(1)).extracting(Something::getId, Something::getName).containsSequence(2, "Brian");
+        assertThat(r.get(2)).extracting(Something::getId, Something::getName).containsSequence(3, "Keith");
+    }
+
+    @Test
+    public void testMultipleExecuteBindFields()
+    {
+        h.registerRowMapper(ConstructorMapper.factory(PublicSomething.class));
+        final PreparedBatch b = h.prepareBatch("insert into something (id, name) values (:id, :name)");
+
+        b.bindFields(new PublicSomething(1, "Eric")).add();
+        b.bindFields(new PublicSomething(2, "Brian")).add();
+        b.execute();
+
+        // bindings should be cleared after execute()
+
+        b.bindFields(new PublicSomething(3, "Keith")).add();
+        b.execute();
+
+        final List<PublicSomething> r = h.createQuery("select * from something order by id").mapTo(PublicSomething.class).list();
+        assertThat(r).hasSize(3);
+        assertThat(r.get(0)).extracting(s -> s.id, s -> s.name).containsSequence(1, "Eric");
+        assertThat(r.get(1)).extracting(s -> s.id, s -> s.name).containsSequence(2, "Brian");
+        assertThat(r.get(2)).extracting(s -> s.id, s -> s.name).containsSequence(3, "Keith");
+    }
+
+    public static class PublicSomething {
+        public int id;
+        public String name;
+
+        @ConstructorProperties({"id", "name"})
+        public PublicSomething(Integer id, String name) {
+            this.id = id;
+            this.name = name;
+        }
+    }
 }
['core/src/test/java/org/jdbi/v3/core/statement/TestPreparedBatch.java', 'core/src/main/java/org/jdbi/v3/core/statement/PreparedBatch.java']