From 5f37ad6f0b259406a24b7dbba336dd96b6f5924f Mon Sep 17 00:00:00 2001
From: terrymanu <terrymanu@163.com>
Date: Fri, 15 Dec 2017 11:58:59 +0800
Subject: [PATCH] for #490

---
 .../pagination/RowNumberDecoratorResultSetMerger.java      | 7 ++++++-
 .../TopAndRowNumberDecoratorResultSetMerger.java           | 7 ++++++-
 .../test/resources/integrate/assert/select_pagination.xml  | 4 ++--
 .../src/test/resources/sql/dql/select_pagination.xml       | 2 +-
 4 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/RowNumberDecoratorResultSetMerger.java b/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/RowNumberDecoratorResultSetMerger.java
index d10ce31dd1132..3eeba44abb04e 100644
--- a/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/RowNumberDecoratorResultSetMerger.java
+++ b/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/RowNumberDecoratorResultSetMerger.java
@@ -43,7 +43,12 @@ public RowNumberDecoratorResultSetMerger(final ResultSetMerger resultSetMerger,
     }
     
     private boolean skipOffset() throws SQLException {
-        int end = limit.getOffset().isBoundOpened() ? limit.getOffsetValue() - 1 : limit.getOffsetValue();
+        int end;
+        if (null == limit.getOffset()) {
+            end = 0;
+        } else {
+            end = limit.getOffset().isBoundOpened() ? limit.getOffsetValue() - 1 : limit.getOffsetValue();
+        }
         for (int i = 0; i < end; i++) {
             if (!getResultSetMerger().next()) {
                 return true;
diff --git a/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/TopAndRowNumberDecoratorResultSetMerger.java b/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/TopAndRowNumberDecoratorResultSetMerger.java
index d0f89e7687832..436b1bc6231b1 100644
--- a/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/TopAndRowNumberDecoratorResultSetMerger.java
+++ b/sharding-jdbc-core/src/main/java/io/shardingjdbc/core/merger/pagination/TopAndRowNumberDecoratorResultSetMerger.java
@@ -43,7 +43,12 @@ public TopAndRowNumberDecoratorResultSetMerger(final ResultSetMerger resultSetMe
     }
     
     private boolean skipOffset() throws SQLException {
-        int end = limit.getOffset().isBoundOpened() ? limit.getOffsetValue() - 1 : limit.getOffsetValue();
+        int end;
+        if (null == limit.getOffset()) {
+            end = 0;
+        } else {
+            end = limit.getOffset().isBoundOpened() ? limit.getOffsetValue() - 1 : limit.getOffsetValue();
+        }
         for (int i = 0; i < end; i++) {
             if (!getResultSetMerger().next()) {
                 return true;
diff --git a/sharding-jdbc-core/src/test/resources/integrate/assert/select_pagination.xml b/sharding-jdbc-core/src/test/resources/integrate/assert/select_pagination.xml
index e29d5c7b9bb34..2e61f62da8e4e 100644
--- a/sharding-jdbc-core/src/test/resources/integrate/assert/select_pagination.xml
+++ b/sharding-jdbc-core/src/test/resources/integrate/assert/select_pagination.xml
@@ -48,12 +48,12 @@
     </sql>
     <sql id="assertSelectSingleTablePaginationWithTopAndRange">
         <sharding-rule>
-            <data parameter="4,2" expected="select/sqlserver/SelectSingleTablePagingWithOffsetAndRowCountSql.xml" />
+            <data parameter="7,3" expected="select/sqlserver/SelectSingleTablePagingWithOffsetAndRowCountSql.xml" />
         </sharding-rule>
     </sql>
     <sql id="assertSelectPaginationWithTopAndRangeWithEqual">
         <sharding-rule>
-            <data parameter="7,10,19,1000,1909,3" expected="select/sqlserver/SelectPagingWithOffsetAndRowCountSql.xml" />
+            <data parameter="4,10,19,1000,1909,3" expected="select/sqlserver/SelectPagingWithOffsetAndRowCountSql.xml" />
         </sharding-rule>
     </sql>
     <sql id="assertSelectSingleTablePaginationWithTopAndRangeWithEqual">
diff --git a/sharding-jdbc-core/src/test/resources/sql/dql/select_pagination.xml b/sharding-jdbc-core/src/test/resources/sql/dql/select_pagination.xml
index 08ebdba8744c1..67c12c6f4c0bb 100644
--- a/sharding-jdbc-core/src/test/resources/sql/dql/select_pagination.xml
+++ b/sharding-jdbc-core/src/test/resources/sql/dql/select_pagination.xml
@@ -8,7 +8,7 @@
     <sql id="assertSelectSingleTablePaginationWithLimit" value="SELECT o.* FROM `t_order` o ORDER BY o.order_id DESC LIMIT %s, %s" type="MySQL,H2" />
     <sql id="assertSelectPaginationWithOffsetAndLimit" value="SELECT i.* FROM t_order o JOIN t_order_item i ON o.user_id = i.user_id AND o.order_id = i.order_id WHERE o.user_id IN (%s, %s) AND o.order_id BETWEEN %s AND %s ORDER BY i.item_id DESC OFFSET %s LIMIT %s" type="PostgreSQL" />
     <sql id="assertSelectPaginationWithTopAndRange" value="SELECT * FROM (SELECT TOP (%s) row_number() OVER (ORDER BY i.item_id DESC) AS rownum_, i.item_id, o.order_id as order_id, o.status as status, o.user_id as user_id FROM t_order o JOIN t_order_item i ON o.user_id = i.user_id AND o.order_id = i.order_id WHERE o.user_id IN (%s, %s) AND o.order_id BETWEEN %s AND %s) AS row_ WHERE row_.rownum_ &gt; %s" type="SQLServer" />
-    <sql id="assertSelectPaginationWithTopAndRangeWithEqual" value="SELECT * FROM (SELECT TOP (%s) row_number() OVER (ORDER BY i.item_id DESC) AS rownum_, i.item_id, o.order_id as order_id, o.status as status, o.user_id as user_id FROM t_order o JOIN t_order_item i ON o.user_id = i.user_id AND o.order_id = i.order_id WHERE o.user_id IN (%s, %s) AND o.order_id BETWEEN %s AND %s) AS row_ WHERE row_.rownum_ &gt; %s" type="SQLServer" />
+    <sql id="assertSelectPaginationWithTopAndRangeWithEqual" value="SELECT * FROM (SELECT TOP (%s) row_number() OVER (ORDER BY i.item_id DESC) AS rownum_, i.item_id, o.order_id as order_id, o.status as status, o.user_id as user_id FROM t_order o JOIN t_order_item i ON o.user_id = i.user_id AND o.order_id = i.order_id WHERE o.user_id IN (%s, %s) AND o.order_id BETWEEN %s AND %s) AS row_ WHERE row_.rownum_ &gt;= %s" type="SQLServer" />
     <sql id="assertSelectSingleTablePaginationWithTopAndRange" value="SELECT * FROM (SELECT TOP (%s) row_number() OVER (ORDER BY o.order_id DESC) AS rownum_, o.order_id as order_id, o.status as status, o.user_id as user_id FROM t_order o) AS row_ WHERE row_.rownum_ &gt; %s" type="SQLServer" />
     <sql id="assertSelectSingleTablePaginationWithTopAndRangeWithEqual" value="SELECT * FROM (SELECT TOP (%s) row_number() OVER (ORDER BY o.order_id DESC) AS rownum_, o.order_id as order_id, o.status as status, o.user_id as user_id FROM t_order o) AS row_ WHERE row_.rownum_ &gt;= %s" type="SQLServer" />
     <sql id="assertSelectPaginationWithRowNumberAndRange" value="SELECT * FROM (SELECT row_.*, rownum rownum_ FROM (SELECT order0_.order_id as order_id, order0_.status as status, order0_.user_id as user_id FROM t_order order0_ JOIN t_order_item i ON order0_.user_id = i.user_id AND order0_.order_id = i.order_id WHERE order0_.user_id IN (%s, %s) AND order0_.order_id BETWEEN %s AND %s ORDER BY i.item_id DESC) row_ WHERE rownum &lt;= %s) t WHERE t.rownum_ &gt; %s" type="Oracle" />