New Oracle12c dialect

Pagination done using offset/fetch

src/NHibernate.Test/DialectTest/Oracle12cDialectFixture.cs

@@ -0,0 +1,95 @@
+using NHibernate.Dialect;
+using NHibernate.SqlCommand;
+using NUnit.Framework;
+
+namespace NHibernate.Test.DialectTest
+{
+	[TestFixture]
+	public class oracle12cDialectFixture
+	{
+		[Test]
+		public void GetLimitString()
+		{
+			var d = new Oracle12cDialect();
+
+			SqlString str = d.GetLimitString(new SqlString("select distinct c.Contact_Id as Contact1_19_0_, c.Rating as Rating2_19_0_, c.Last_Name as Last_Name3_19_0, c.First_Name as First_Name4_19_0 from dbo.Contact c where COALESCE(c.Rating, 0) > 0 order by c.Rating desc , c.Last_Name , c.First_Name"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"select distinct c.Contact_Id as Contact1_19_0_, c.Rating as Rating2_19_0_, c.Last_Name as Last_Name3_19_0, c.First_Name as First_Name4_19_0 from dbo.Contact c where COALESCE(c.Rating, 0) > 0 order by c.Rating desc , c.Last_Name , c.First_Name OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT fish.id FROM fish"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT fish.id FROM fish OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT DISTINCT fish_.id FROM fish fish_"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT DISTINCT fish_.id FROM fish fish_ OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT DISTINCT fish_.id as ixx9_ FROM fish fish_"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT DISTINCT fish_.id as ixx9_ FROM fish fish_ OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT * FROM fish ORDER BY name"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT * FROM fish ORDER BY name OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT fish.id, fish.name FROM fish ORDER BY name DESC"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT fish.id, fish.name FROM fish ORDER BY name DESC OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT * FROM fish LEFT JOIN (SELECT * FROM meat ORDER BY weight) AS t ORDER BY name DESC"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT * FROM fish LEFT JOIN (SELECT * FROM meat ORDER BY weight) AS t ORDER BY name DESC OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT *, (SELECT COUNT(1) FROM fowl WHERE fish_id = fish.id) AS some_count FROM fish"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT *, (SELECT COUNT(1) FROM fowl WHERE fish_id = fish.id) AS some_count FROM fish OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT * FROM fish WHERE scales = ", Parameter.Placeholder), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT * FROM fish WHERE scales = ? OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+
+			str = d.GetLimitString(new SqlString("SELECT f.Type, COUNT(DISTINCT f.Name) AS Name FROM Fish f GROUP BY f.Type ORDER BY COUNT(DISTINCT f.Name)"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT f.Type, COUNT(DISTINCT f.Name) AS Name FROM Fish f GROUP BY f.Type ORDER BY COUNT(DISTINCT f.Name) OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+		}
+
+		[Test]
+		public void GetLimitStringWithInnerOrder()
+		{
+			var d = new Oracle12cDialect();
+
+			var str = d.GetLimitString(new SqlString("SELECT * FROM A LEFT JOIN (SELECT top 7 * FROM B ORDER BY name) AS B on A.Name = B.Name"), new SqlString("111"), new SqlString("222"));
+			Assert.AreEqual(
+				"SELECT * FROM A LEFT JOIN (SELECT top 7 * FROM B ORDER BY name) AS B on A.Name = B.Name OFFSET 111 ROWS FETCH FIRST 222 ROWS ONLY",
+				str.ToString());
+		}
+
+		[Test]
+		public void OnlyOffsetLimit()
+		{
+			var d = new Oracle12cDialect();
+
+			SqlString str = d.GetLimitString(new SqlString("select distinct c.Contact_Id as Contact1_19_0_, c._Rating as Rating2_19_0_ from dbo.Contact c where COALESCE(c.Rating, 0) > 0 order by c.Rating desc , c.Last_Name , c.First_Name"), null, new SqlString("10"));
+			Assert.That(str.ToString(), Is.EqualTo("select distinct c.Contact_Id as Contact1_19_0_, c._Rating as Rating2_19_0_ from dbo.Contact c where COALESCE(c.Rating, 0) > 0 order by c.Rating desc , c.Last_Name , c.First_Name FETCH FIRST 10 ROWS ONLY"));
+		}
+
+		[Test]
+		public void GetLimitStringWithSqlComments()
+		{
+			var d = new Oracle12cDialect();
+			var limitSqlQuery = d.GetLimitString(new SqlString(" /* criteria query */ SELECT p from lcdtm"), null, new SqlString("2"));
+			Assert.That(limitSqlQuery, Is.Not.Null);
+			Assert.That(limitSqlQuery.ToString(), Is.EqualTo(" /* criteria query */ SELECT p from lcdtm FETCH FIRST 2 ROWS ONLY"));
+		}
+	}
+}

src/NHibernate.Test/NHibernate.Test.csproj

@@ -230,6 +230,7 @@
     <Compile Include="DialectTest\FunctionTests\SubstringSupportFixture.cs" />
     <Compile Include="DialectTest\FunctionTests\SequenceSupportFixture.cs" />
     <Compile Include="DialectTest\Ingres9DialectFixture.cs" />
+    <Compile Include="DialectTest\Oracle12cDialectFixture.cs" />
     <Compile Include="DialectTest\MsSql2012DialectFixture.cs" />
     <Compile Include="DialectTest\LockHintAppenderFixture.cs" />
     <Compile Include="DialectTest\MsSqlCe40DialectFixture.cs" />

src/NHibernate/Dialect/Oracle12cDialect.cs

@@ -0,0 +1,42 @@
+using NHibernate.SqlCommand;
+
+namespace NHibernate.Dialect
+{
+	/// <summary> 
+	/// A dialect specifically for use with Oracle 10g.
+	/// </summary>
+	/// <remarks>
+	/// The main difference between this dialect and <see cref="Oracle12cDialect"/>
+	/// is the use of "ANSI join syntax" here...
+	/// </remarks>
+	public class Oracle12cDialect : Oracle10gDialect
+	{
+		/// <summary>
+		/// Oracle 12c supports a query statement that provides <c>LIMIT</c>
+		/// functionality with an offset.
+		/// </summary>
+		/// <value><c>false</c></value>
+		public override bool UseMaxForLimit
+		{
+			get { return false; }
+		}
+
+		public override SqlString GetLimitString(SqlString querySqlString, SqlString offset, SqlString limit)
+		{
+			var result = new SqlStringBuilder(querySqlString);
+
+			if (offset != null)
+			{
+				result.Add(" OFFSET ");
+				result.Add(offset).Add(" ROWS");
+			}
+
+			if (limit != null)
+			{
+				result.Add(" FETCH FIRST ").Add(limit).Add(" ROWS ONLY");
+			}
+
+			return result.ToSqlString();
+		}
+	}
+}

src/NHibernate/NHibernate.csproj

@@ -158,6 +158,7 @@
     <Compile Include="Dialect\MySQL5InnoDBDialect.cs" />
     <Compile Include="Dialect\MySQLDialect.cs" />
     <Compile Include="Dialect\BitwiseNativeOperation.cs" />
+    <Compile Include="Dialect\Oracle12cDialect.cs" />
     <Compile Include="Dialect\PostgreSQLDialect.cs" />
     <Compile Include="Dialect\Schema\PostgreSQLMetadata.cs" />
     <Compile Include="Dialect\Schema\SchemaHelper.cs" />