diff --git a/src/main/java/com/noorq/casser/core/Casser.java b/src/main/java/com/noorq/casser/core/Casser.java
index 998945c..ab87065 100644
--- a/src/main/java/com/noorq/casser/core/Casser.java
+++ b/src/main/java/com/noorq/casser/core/Casser.java
@@ -47,8 +47,10 @@ public final class Casser {
 		return Objects.requireNonNull(session, "session is not initialized");
 	}
 	
-	protected static void register(CasserSession newSession) {
-		session = newSession;
+	protected static synchronized void register(CasserSession newSession) {
+		if (session == null) {
+			session = newSession;
+		}
 	}
 	
 	public static CasserSettings settings() {
diff --git a/src/main/java/com/noorq/casser/core/Postulate.java b/src/main/java/com/noorq/casser/core/Postulate.java
index 5698350..3b97dbf 100644
--- a/src/main/java/com/noorq/casser/core/Postulate.java
+++ b/src/main/java/com/noorq/casser/core/Postulate.java
@@ -15,12 +15,13 @@
  */
 package com.noorq.casser.core;
 
+import java.util.Arrays;
+
 import com.datastax.driver.core.querybuilder.Clause;
 import com.datastax.driver.core.querybuilder.QueryBuilder;
 import com.noorq.casser.core.reflect.CasserPropertyNode;
 import com.noorq.casser.mapping.value.ColumnValuePreparer;
 import com.noorq.casser.support.CasserMappingException;
-import com.noorq.casser.support.Requires;
 
 public final class Postulate<V> {
 
@@ -28,7 +29,6 @@ public final class Postulate<V> {
 	private final V[] values;
 	
 	protected Postulate(Operator op, V[] values) {
-		Requires.nonNullArray(values);
 		this.operator = op;
 		this.values = values;
     }
@@ -78,7 +78,22 @@ public final class Postulate<V> {
 	public String toString() {
 		
 		if (operator == Operator.IN) {
-			return "in(" + values + ")";
+			
+			if (values == null) {
+				return "in()";
+			}
+			
+			int len = values.length;
+	        StringBuilder b = new StringBuilder();
+	        b.append("in(");
+	        for (int i = 0; i != len; i++) {
+	        	if (b.length() > 3) {
+		            b.append(", ");
+	        	}
+	            b.append(String.valueOf(values[i]));
+	        }
+            return b.append(')').toString();
+			
 		}
 		
 		return operator.getName() + values[0];
diff --git a/src/main/java/com/noorq/casser/core/SessionInitializer.java b/src/main/java/com/noorq/casser/core/SessionInitializer.java
index e4c874e..8fa496d 100644
--- a/src/main/java/com/noorq/casser/core/SessionInitializer.java
+++ b/src/main/java/com/noorq/casser/core/SessionInitializer.java
@@ -166,10 +166,7 @@ public final class SessionInitializer extends AbstractSessionOperations {
 		return this;
 	}
 	
-	public synchronized void register() {
-		if (Casser.session() != null) {
-			return;
-		}
+	public void register() {
 		Casser.register(get());
 	}
 	
diff --git a/src/main/java/com/noorq/casser/core/operation/UpdateOperation.java b/src/main/java/com/noorq/casser/core/operation/UpdateOperation.java
index 25ef568..2073dae 100644
--- a/src/main/java/com/noorq/casser/core/operation/UpdateOperation.java
+++ b/src/main/java/com/noorq/casser/core/operation/UpdateOperation.java
@@ -339,7 +339,7 @@ public final class UpdateOperation extends AbstractFilterOperation<ResultSet, Up
 	public BuiltStatement buildStatement() {
 		
 		if (entity == null) {
-			throw new CasserMappingException("unknown entity");
+			throw new CasserMappingException("empty update operation");
 		}
 		
 		Update update = QueryBuilder.update(entity.getName().toCql());
diff --git a/src/test/java/com/noorq/casser/test/integration/core/simple/Message.java b/src/test/java/com/noorq/casser/test/integration/core/simple/Message.java
new file mode 100644
index 0000000..2a22962
--- /dev/null
+++ b/src/test/java/com/noorq/casser/test/integration/core/simple/Message.java
@@ -0,0 +1,46 @@
+/*
+ *      Copyright (C) 2015 Noorq, Inc.
+ *
+ *   Licensed under the Apache License, Version 2.0 (the "License");
+ *   you may not use this file except in compliance with the License.
+ *   You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing, software
+ *   distributed under the License is distributed on an "AS IS" BASIS,
+ *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   See the License for the specific language governing permissions and
+ *   limitations under the License.
+ */
+package com.noorq.casser.test.integration.core.simple;
+
+import java.util.Date;
+
+import com.noorq.casser.mapping.annotation.ClusteringColumn;
+import com.noorq.casser.mapping.annotation.Column;
+import com.noorq.casser.mapping.annotation.PartitionKey;
+import com.noorq.casser.mapping.annotation.StaticColumn;
+import com.noorq.casser.mapping.annotation.Table;
+import com.noorq.casser.mapping.annotation.Types;
+
+@Table
+public interface Message {
+
+	@PartitionKey
+	int id();
+
+	@ClusteringColumn
+	@Types.Timeuuid
+	Date timestamp();
+	
+	@StaticColumn(forceQuote=true)
+	String from();
+	
+	@Column(forceQuote=true)
+	String to();
+
+	@Column
+	String message();
+
+}
diff --git a/src/test/java/com/noorq/casser/test/integration/core/simple/StaticColumnTest.java b/src/test/java/com/noorq/casser/test/integration/core/simple/StaticColumnTest.java
new file mode 100644
index 0000000..6f08f1f
--- /dev/null
+++ b/src/test/java/com/noorq/casser/test/integration/core/simple/StaticColumnTest.java
@@ -0,0 +1,158 @@
+/*
+ *      Copyright (C) 2015 Noorq, Inc.
+ *
+ *   Licensed under the Apache License, Version 2.0 (the "License");
+ *   you may not use this file except in compliance with the License.
+ *   You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing, software
+ *   distributed under the License is distributed on an "AS IS" BASIS,
+ *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *   See the License for the specific language governing permissions and
+ *   limitations under the License.
+ */
+package com.noorq.casser.test.integration.core.simple;
+
+import static com.noorq.casser.core.Query.eq;
+
+import java.util.Date;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import com.noorq.casser.core.Casser;
+import com.noorq.casser.test.integration.build.AbstractEmbeddedCassandraTest;
+
+public class StaticColumnTest extends AbstractEmbeddedCassandraTest {
+
+	static Message message = Casser.dsl(Message.class);
+	
+	@BeforeClass
+	public static void beforeTest() {
+		Casser.init(getSession()).showCql().add(Message.class).autoCreateDrop().register();
+	}
+	
+	@Test
+	public void testPrint() {
+		System.out.println(message);
+	}
+	
+	private static class MessageImpl implements Message {
+		
+		int id;
+		Date timestamp;
+		String from;
+		String to;
+		String msg;
+		
+		@Override
+		public int id() {
+			return id;
+		}
+
+		@Override
+		public Date timestamp() {
+			return timestamp;
+		}
+
+		@Override
+		public String from() {
+			return from;
+		}
+
+		@Override
+		public String to() {
+			return to;
+		}
+
+		@Override
+		public String message() {
+			return msg;
+		}
+		
+	}
+	
+	
+	@Test
+	public void testCRUID() {
+		
+		MessageImpl msg = new MessageImpl();
+		msg.id = 123;
+		msg.timestamp = new Date();
+		msg.from = "Alex";
+		msg.to = "Bob";
+		msg.msg = "hi";
+		
+		// CREATE
+		
+		Casser.session().insert(msg).sync();
+		
+		msg.id = 123;
+		msg.to = "Craig";
+
+		Casser.session().insert(msg).sync();
+		
+		
+		// READ
+		
+		List<Message> actual = Casser.session().select(Message.class)
+				.where(message::id, eq(123)).sync()
+				.collect(Collectors.toList());
+		
+		Assert.assertEquals(2, actual.size());
+		
+		Message toCraig = actual.stream().filter(m -> m.to().equals("Craig")).findFirst().get();		
+		assertMessages(msg, toCraig);
+		
+		// UPDATE
+		
+		Casser.session().update().set(message::from, "Albert")
+		.where(message::id, eq(123))
+		.onlyIf(message::from, eq("Alex"))
+		.sync();
+		
+		long cnt = Casser.session().select(message::from)
+				.where(message::id, eq(123)).sync()
+				.filter(t -> t._1.equals("Albert"))
+				.count();
+		
+		Assert.assertEquals(2, cnt);
+
+		// INSERT
+		
+		Casser.session().update().set(message::from, null)
+			.where(message::id, eq(123))
+			.sync();
+		
+		Casser.session().select(message::from)
+				.where(message::id, eq(123))
+				.sync()
+				.map(t -> t._1)
+				.forEach(Assert::assertNull);
+
+		Casser.session().update().set(message::from, "Alex")
+			.where(message::id, eq(123))
+			.onlyIf(message::from, eq(null)).sync();
+		
+		// DELETE
+		
+		Casser.session().delete().where(message::id, eq(123)).sync();
+		
+		cnt = Casser.session().count().where(message::id, eq(123)).sync();
+		Assert.assertEquals(0, cnt);
+	}
+	
+	private void assertMessages(Message expected, Message actual) {
+		Assert.assertEquals(expected.id(), actual.id());
+		Assert.assertEquals(expected.from(), actual.from());
+		Assert.assertEquals(expected.timestamp(), actual.timestamp());
+		Assert.assertEquals(expected.to(), actual.to());
+		Assert.assertEquals(expected.message(), actual.message());
+	}
+	
+}