diff --git a/sharding-core/src/main/java/io/shardingsphere/core/rule/ShardingRule.java b/sharding-core/src/main/java/io/shardingsphere/core/rule/ShardingRule.java
index 752caeae17bc23239f008288cc0b652657a5eaa3..a8858d1fbd1217aab104b29a4a6f14990c199f29 100644
--- a/sharding-core/src/main/java/io/shardingsphere/core/rule/ShardingRule.java
+++ b/sharding-core/src/main/java/io/shardingsphere/core/rule/ShardingRule.java
@@ -27,7 +27,7 @@ import io.shardingsphere.api.config.rule.TableRuleConfiguration;
 import io.shardingsphere.api.config.strategy.ShardingStrategyConfiguration;
 import io.shardingsphere.core.exception.ShardingConfigurationException;
 import io.shardingsphere.core.exception.ShardingException;
-import io.shardingsphere.core.keygen.DefaultKeyGenerator;
+import io.shardingsphere.core.keygen.SnowflakeKeyGenerator;
 import io.shardingsphere.core.keygen.KeyGenerator;
 import io.shardingsphere.core.parsing.parser.context.condition.Column;
 import io.shardingsphere.core.routing.strategy.ShardingStrategy;
@@ -111,7 +111,7 @@ public class ShardingRule {
     }
     
     private KeyGenerator createDefaultKeyGenerator(final KeyGenerator defaultKeyGenerator) {
-        return null == defaultKeyGenerator ? new DefaultKeyGenerator() : defaultKeyGenerator;
+        return null == defaultKeyGenerator ? new SnowflakeKeyGenerator() : defaultKeyGenerator;
     }
     
     private Collection<MasterSlaveRule> createMasterSlaveRules(final Collection<MasterSlaveRuleConfiguration> masterSlaveRuleConfigurations) {
diff --git a/sharding-core/src/test/java/io/shardingsphere/core/rule/ShardingRuleTest.java b/sharding-core/src/test/java/io/shardingsphere/core/rule/ShardingRuleTest.java
index 35ec2b84cdf39e27a529c93e4c62d1e31a7af692..07782182fc21b2f6e97df7e712f89676a6bae624 100644
--- a/sharding-core/src/test/java/io/shardingsphere/core/rule/ShardingRuleTest.java
+++ b/sharding-core/src/test/java/io/shardingsphere/core/rule/ShardingRuleTest.java
@@ -26,7 +26,7 @@ import io.shardingsphere.api.config.strategy.InlineShardingStrategyConfiguration
 import io.shardingsphere.api.config.strategy.NoneShardingStrategyConfiguration;
 import io.shardingsphere.api.config.strategy.StandardShardingStrategyConfiguration;
 import io.shardingsphere.core.exception.ShardingConfigurationException;
-import io.shardingsphere.core.keygen.DefaultKeyGenerator;
+import io.shardingsphere.core.keygen.SnowflakeKeyGenerator;
 import io.shardingsphere.core.keygen.fixture.IncrementKeyGenerator;
 import io.shardingsphere.core.parsing.parser.context.condition.Column;
 import io.shardingsphere.core.routing.strategy.inline.InlineShardingStrategy;
@@ -73,7 +73,7 @@ public final class ShardingRuleTest {
         assertTrue(actual.getBroadcastTables().isEmpty());
         assertThat(actual.getDefaultDatabaseShardingStrategy(), instanceOf(NoneShardingStrategy.class));
         assertThat(actual.getDefaultTableShardingStrategy(), instanceOf(NoneShardingStrategy.class));
-        assertThat(actual.getDefaultKeyGenerator(), instanceOf(DefaultKeyGenerator.class));
+        assertThat(actual.getDefaultKeyGenerator(), instanceOf(SnowflakeKeyGenerator.class));
     }
     
     @Test
diff --git a/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingConfigurationTest.java b/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingConfigurationTest.java
index aa770230ec76c9232954dc5370c0ce72938d4670..d7d8ebe2aa35aae513d6927bc56e0065592961a2 100644
--- a/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingConfigurationTest.java
+++ b/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingConfigurationTest.java
@@ -18,7 +18,7 @@
 package io.shardingsphere.core.yaml.sharding;
 
 import io.shardingsphere.api.algorithm.masterslave.MasterSlaveLoadBalanceAlgorithmType;
-import io.shardingsphere.core.keygen.DefaultKeyGenerator;
+import io.shardingsphere.core.keygen.SnowflakeKeyGenerator;
 import org.hamcrest.CoreMatchers;
 import org.junit.Test;
 
@@ -105,7 +105,7 @@ public final class YamlShardingConfigurationTest {
         assertThat(actual.getShardingRule().getTables().get("t_order").getTableStrategy().getInline().getShardingColumn(), is("order_id"));
         assertThat(actual.getShardingRule().getTables().get("t_order").getTableStrategy().getInline().getAlgorithmExpression(), is("t_order_${order_id % 2}"));
         assertThat(actual.getShardingRule().getTables().get("t_order").getKeyGenerator().getColumn(), is("order_id"));
-        assertThat(actual.getShardingRule().getTables().get("t_order").getKeyGenerator().getClassName(), is(DefaultKeyGenerator.class.getName()));
+        assertThat(actual.getShardingRule().getTables().get("t_order").getKeyGenerator().getClassName(), is(SnowflakeKeyGenerator.class.getName()));
         assertThat(actual.getShardingRule().getTables().get("t_order").getLogicIndex(), is("order_index"));
     }
     
@@ -130,7 +130,7 @@ public final class YamlShardingConfigurationTest {
         assertThat(actual.getShardingRule().getDefaultDataSourceName(), is("default_ds"));
         assertThat(actual.getShardingRule().getDefaultDatabaseStrategy().getInline().getShardingColumn(), is("order_id"));
         assertThat(actual.getShardingRule().getDefaultDatabaseStrategy().getInline().getAlgorithmExpression(), is("ds_${order_id % 2}"));
-        assertThat(actual.getShardingRule().getDefaultKeyGenerator().getKeyGenerator().getClass().getName(), is(DefaultKeyGenerator.class.getName()));
+        assertThat(actual.getShardingRule().getDefaultKeyGenerator().getKeyGenerator().getClass().getName(), is(SnowflakeKeyGenerator.class.getName()));
     }
     
     private void assertMasterSlaveRules(final YamlShardingConfiguration actual) {
diff --git a/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingRuleConfigurationTest.java b/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingRuleConfigurationTest.java
index 1ee9e8b09db317d64f0d68f92c98af151ab08043..b7e3aeedf589f28600653ea758f080a101d16abe 100644
--- a/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingRuleConfigurationTest.java
+++ b/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlShardingRuleConfigurationTest.java
@@ -23,7 +23,7 @@ import io.shardingsphere.api.config.rule.MasterSlaveRuleConfiguration;
 import io.shardingsphere.api.config.rule.ShardingRuleConfiguration;
 import io.shardingsphere.api.config.rule.TableRuleConfiguration;
 import io.shardingsphere.api.config.strategy.NoneShardingStrategyConfiguration;
-import io.shardingsphere.core.keygen.DefaultKeyGenerator;
+import io.shardingsphere.core.keygen.SnowflakeKeyGenerator;
 import io.shardingsphere.core.yaml.masterslave.YamlMasterSlaveRuleConfiguration;
 import io.shardingsphere.core.yaml.sharding.strategy.YamlNoneShardingStrategyConfiguration;
 import org.hamcrest.CoreMatchers;
@@ -62,7 +62,7 @@ public final class YamlShardingRuleConfigurationTest {
         result.getBindingTables().add("t_order, t_order_item");
         result.getBroadcastTables().add("t_config");
         YamlKeyGeneratorConfiguration keyGeneratorConfiguration = new YamlKeyGeneratorConfiguration();
-        keyGeneratorConfiguration.setClassName(DefaultKeyGenerator.class.getName());
+        keyGeneratorConfiguration.setClassName(SnowflakeKeyGenerator.class.getName());
         result.setDefaultKeyGenerator(keyGeneratorConfiguration);
         result.getMasterSlaveRules().put("master_slave_ds", createYamlMasterSlaveRuleConfig());
         return result;
@@ -97,7 +97,7 @@ public final class YamlShardingRuleConfigurationTest {
         assertThat(actual.getBindingTableGroups().iterator().next(), is("t_order, t_order_item"));
         assertThat(actual.getBroadcastTables().size(), is(1));
         assertThat(actual.getBroadcastTables().iterator().next(), is("t_config"));
-        assertThat(actual.getDefaultKeyGenerator(), instanceOf(DefaultKeyGenerator.class));
+        assertThat(actual.getDefaultKeyGenerator(), instanceOf(SnowflakeKeyGenerator.class));
         assertMasterSlaveRuleConfig(actual.getMasterSlaveRuleConfigs().iterator().next());
     }
     
diff --git a/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlTableRuleConfigurationTest.java b/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlTableRuleConfigurationTest.java
index 4c5bd3d4509da55da7b9b92ac1bb9a0718bb4166..6cd9555ea53846250aae5427fa6538c29d1564f3 100644
--- a/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlTableRuleConfigurationTest.java
+++ b/sharding-core/src/test/java/io/shardingsphere/core/yaml/sharding/YamlTableRuleConfigurationTest.java
@@ -19,7 +19,7 @@ package io.shardingsphere.core.yaml.sharding;
 
 import io.shardingsphere.api.config.rule.TableRuleConfiguration;
 import io.shardingsphere.api.config.strategy.NoneShardingStrategyConfiguration;
-import io.shardingsphere.core.keygen.DefaultKeyGenerator;
+import io.shardingsphere.core.keygen.SnowflakeKeyGenerator;
 import io.shardingsphere.core.yaml.sharding.strategy.YamlNoneShardingStrategyConfiguration;
 import org.junit.Test;
 
@@ -55,7 +55,7 @@ public final class YamlTableRuleConfigurationTest {
         result.setActualDataNodes("ds_${0..1}.t_order_${0..1}");
         result.setKeyGenerator(new YamlKeyGeneratorConfiguration());
         result.getKeyGenerator().setColumn("order_id");
-        result.getKeyGenerator().setClassName(DefaultKeyGenerator.class.getName());
+        result.getKeyGenerator().setClassName(SnowflakeKeyGenerator.class.getName());
         result.setLogicIndex("order_index");
         return result;
     }
@@ -73,7 +73,7 @@ public final class YamlTableRuleConfigurationTest {
         assertThat(actual.getLogicTable(), is("t_order"));
         assertThat(actual.getActualDataNodes(), is("ds_${0..1}.t_order_${0..1}"));
         assertThat(actual.getKeyGeneratorColumnName(), is("order_id"));
-        assertThat(actual.getKeyGenerator(), instanceOf(DefaultKeyGenerator.class));
+        assertThat(actual.getKeyGenerator(), instanceOf(SnowflakeKeyGenerator.class));
         assertThat(actual.getLogicIndex(), is("order_index"));
     }