diff --git a/components/device-mgt/io.entgra.device.mgt.core.device.mgt.common/src/main/java/io/entgra/device/mgt/core/device/mgt/common/DeviceIdentifier.java b/components/device-mgt/io.entgra.device.mgt.core.device.mgt.common/src/main/java/io/entgra/device/mgt/core/device/mgt/common/DeviceIdentifier.java
index a1bb3fe51e3..d02f844071e 100644
--- a/components/device-mgt/io.entgra.device.mgt.core.device.mgt.common/src/main/java/io/entgra/device/mgt/core/device/mgt/common/DeviceIdentifier.java
+++ b/components/device-mgt/io.entgra.device.mgt.core.device.mgt.common/src/main/java/io/entgra/device/mgt/core/device/mgt/common/DeviceIdentifier.java
@@ -69,9 +69,20 @@ public class DeviceIdentifier implements Serializable{
 
     @Override
     public String toString() {
-        return "deviceId {" +
-                "id='" + id + '\'' +
-                ", type='" + type + '\'' +
-                '}';
+        return type + "|" + id;
     }
+
+    @Override
+    public int hashCode() {
+        return toString().hashCode();
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof DeviceIdentifier) {
+            return (this.hashCode() == obj.hashCode());
+        }
+        return false;
+    }
+
 }
diff --git a/components/device-mgt/io.entgra.device.mgt.core.device.mgt.core/src/main/java/io/entgra/device/mgt/core/device/mgt/core/cache/DeviceCacheKey.java b/components/device-mgt/io.entgra.device.mgt.core.device.mgt.core/src/main/java/io/entgra/device/mgt/core/device/mgt/core/cache/DeviceCacheKey.java
index a5931f408e3..d25cd2673a2 100644
--- a/components/device-mgt/io.entgra.device.mgt.core.device.mgt.core/src/main/java/io/entgra/device/mgt/core/device/mgt/core/cache/DeviceCacheKey.java
+++ b/components/device-mgt/io.entgra.device.mgt.core.device.mgt.core/src/main/java/io/entgra/device/mgt/core/device/mgt/core/cache/DeviceCacheKey.java
@@ -28,7 +28,6 @@ public class DeviceCacheKey {
     private String deviceId;
     private String deviceType;
     private int tenantId;
-    private volatile int hashCode;
 
     public String getDeviceId() {
         return deviceId;
@@ -55,27 +54,21 @@ public class DeviceCacheKey {
     }
 
     @Override
-    public boolean equals(Object obj) {
-        if (obj == null) {
-            return false;
-        }
-        if (!DeviceCacheKey.class.isAssignableFrom(obj.getClass())) {
-            return false;
-        }
-        final DeviceCacheKey other = (DeviceCacheKey) obj;
-        String thisId = this.deviceId + "-" + this.deviceType + "_" + this.tenantId;
-        String otherId = other.deviceId + "-" + other.deviceType + "_" + other.tenantId;
-        if (!thisId.equals(otherId)) {
-            return false;
-        }
-        return true;
+    public int hashCode() {
+        return toString().hashCode();
     }
 
     @Override
-    public int hashCode() {
-        if (hashCode == 0) {
-            hashCode = Objects.hash(deviceId, deviceType, tenantId);
+    public String toString() {
+        return tenantId + "|" + deviceType + "|" + deviceId;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof DeviceCacheKey) {
+            return (this.hashCode() == obj.hashCode());
         }
-        return hashCode;
+        return false;
     }
+
 }
diff --git a/components/heartbeat-management/io.entgra.device.mgt.core.server.bootup.heartbeat.beacon/src/main/java/io/entgra/device/mgt/core/server/bootup/heartbeat/beacon/dao/HeartBeatBeaconDAOFactory.java b/components/heartbeat-management/io.entgra.device.mgt.core.server.bootup.heartbeat.beacon/src/main/java/io/entgra/device/mgt/core/server/bootup/heartbeat/beacon/dao/HeartBeatBeaconDAOFactory.java
index 7130f07cbfd..e3c3dd3381b 100644
--- a/components/heartbeat-management/io.entgra.device.mgt.core.server.bootup.heartbeat.beacon/src/main/java/io/entgra/device/mgt/core/server/bootup/heartbeat/beacon/dao/HeartBeatBeaconDAOFactory.java
+++ b/components/heartbeat-management/io.entgra.device.mgt.core.server.bootup.heartbeat.beacon/src/main/java/io/entgra/device/mgt/core/server/bootup/heartbeat/beacon/dao/HeartBeatBeaconDAOFactory.java
@@ -24,10 +24,8 @@ import io.entgra.device.mgt.core.server.bootup.heartbeat.beacon.config.datasourc
 import io.entgra.device.mgt.core.server.bootup.heartbeat.beacon.dao.impl.GenericHeartBeatDAOImpl;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import io.entgra.device.mgt.core.device.mgt.common.DeviceManagementConstants;
 import io.entgra.device.mgt.core.device.mgt.common.exceptions.IllegalTransactionStateException;
 import io.entgra.device.mgt.core.device.mgt.common.exceptions.TransactionManagementException;
-import io.entgra.device.mgt.core.device.mgt.common.exceptions.UnsupportedDatabaseEngineException;
 
 import javax.sql.DataSource;
 import java.sql.Connection;
@@ -42,7 +40,7 @@ public class HeartBeatBeaconDAOFactory {
 
     private static final Log log = LogFactory.getLog(HeartBeatBeaconDAOFactory.class);
     private static DataSource dataSource;
-    private static ThreadLocal<Connection> currentConnection = new ThreadLocal<>();
+    private static final ThreadLocal<Connection> currentConnection = new ThreadLocal<>();
 
     /**
      * Get instance of GroupDAO
@@ -64,7 +62,6 @@ public class HeartBeatBeaconDAOFactory {
     /**
      * Begin transaction with datasource for write data
      *
-     * @throws TransactionManagementException
      */
     public static void beginTransaction() throws TransactionManagementException {
         Connection conn = currentConnection.get();
@@ -85,7 +82,6 @@ public class HeartBeatBeaconDAOFactory {
     /**
      * Open connection to the datasource for read data
      *
-     * @throws SQLException
      */
     public static void openConnection() throws SQLException {
         Connection conn = currentConnection.get();
@@ -102,7 +98,6 @@ public class HeartBeatBeaconDAOFactory {
      * Get current connection to datasource
      *
      * @return current connection
-     * @throws SQLException
      */
     public static Connection getConnection() throws SQLException {
         Connection conn = currentConnection.get();
@@ -189,7 +184,7 @@ public class HeartBeatBeaconDAOFactory {
             List<JNDILookupDefinition.JNDIProperty> jndiPropertyList =
                     jndiConfig.getJndiProperties();
             if (jndiPropertyList != null) {
-                Hashtable<Object, Object> jndiProperties = new Hashtable<Object, Object>();
+                Hashtable<Object, Object> jndiProperties = new Hashtable<>();
                 for (JNDILookupDefinition.JNDIProperty prop : jndiPropertyList) {
                     jndiProperties.put(prop.getName(), prop.getValue());
                 }
diff --git a/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/cache/OperationTemplateCacheLoader.java b/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/cache/OperationTemplateCacheLoader.java
index e92ffbadccd..4b9316fad92 100644
--- a/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/cache/OperationTemplateCacheLoader.java
+++ b/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/cache/OperationTemplateCacheLoader.java
@@ -59,9 +59,8 @@ public class OperationTemplateCacheLoader extends CacheLoader<String, OperationT
         String deviceType = operationTemplateCacheKey.getDeviceType();
 
         if (log.isTraceEnabled()) {
-            log.trace(
-                    "Loading operation template for subtype Id : " + subTypeId + " & deviceType : " + deviceType + " operation code : "
-                            + operationCode);
+            log.trace("Loading operation template for subtype Id : " + subTypeId
+                    + " & deviceType : " + deviceType + " operation code : " + operationCode);
         }
         try {
             ConnectionManagerUtils.openDBConnection();
diff --git a/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/dto/OperationTemplateCacheKey.java b/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/dto/OperationTemplateCacheKey.java
index 3f0da031a13..928210f88a9 100644
--- a/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/dto/OperationTemplateCacheKey.java
+++ b/components/operation-template-mgt/io.entgra.device.mgt.core.operation.template/src/main/java/io/entgra/device/mgt/core/operation/template/dto/OperationTemplateCacheKey.java
@@ -47,4 +47,23 @@ public class OperationTemplateCacheKey {
     public void setDeviceType(String deviceType) {
         this.deviceType = deviceType;
     }
+
+    @Override
+    public int hashCode() {
+        return toString().hashCode();
+    }
+
+    @Override
+    public String toString() {
+        return subTypeId + "|" + deviceType + "|" + operationCode;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof OperationTemplateCacheKey) {
+            return (this.hashCode() == obj.hashCode());
+        }
+        return false;
+    }
+
 }
diff --git a/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/dto/DeviceSubTypeCacheKey.java b/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/dto/DeviceSubTypeCacheKey.java
index 925f82d655b..68414b154c8 100644
--- a/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/dto/DeviceSubTypeCacheKey.java
+++ b/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/dto/DeviceSubTypeCacheKey.java
@@ -58,4 +58,12 @@ public class DeviceSubTypeCacheKey {
         return tenantId + "|" + subTypeId + "|" + deviceType;
     }
 
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof DeviceSubTypeCacheKey) {
+            return (this.hashCode() == obj.hashCode());
+        }
+        return false;
+    }
+
 }
diff --git a/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/impl/DeviceSubTypeServiceImpl.java b/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/impl/DeviceSubTypeServiceImpl.java
index b434cfbb2d3..4e5d855a230 100644
--- a/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/impl/DeviceSubTypeServiceImpl.java
+++ b/components/subtype-mgt/io.entgra.device.mgt.core.subtype.mgt/src/main/java/io/entgra/device/mgt/core/subtype/mgt/impl/DeviceSubTypeServiceImpl.java
@@ -42,7 +42,9 @@ import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 
 public class DeviceSubTypeServiceImpl implements DeviceSubTypeService {
+
     private static final Log log = LogFactory.getLog(DeviceSubTypeServiceImpl.class);
+
     private static final LoadingCache<DeviceSubTypeCacheKey, DeviceSubType> deviceSubTypeCache
             = CacheBuilder.newBuilder()
             .expireAfterWrite(15, TimeUnit.MINUTES)
@@ -143,7 +145,7 @@ public class DeviceSubTypeServiceImpl implements DeviceSubTypeService {
     }
 
     @Override
-    public DeviceSubType getDeviceSubType(String subTypeId, int tenantId, String deviceType)
+    public synchronized DeviceSubType getDeviceSubType(String subTypeId, int tenantId, String deviceType)
             throws SubTypeMgtPluginException {
         try {
             DeviceSubTypeCacheKey key = DeviceSubTypeMgtUtil.getDeviceSubTypeCacheKey(tenantId, subTypeId, deviceType);
diff --git a/features/device-mgt/io.entgra.device.mgt.core.device.mgt.basics.feature/src/main/resources/dbscripts/cdm/mysql.sql b/features/device-mgt/io.entgra.device.mgt.core.device.mgt.basics.feature/src/main/resources/dbscripts/cdm/mysql.sql
index 9d3751e5d79..70005138334 100644
--- a/features/device-mgt/io.entgra.device.mgt.core.device.mgt.basics.feature/src/main/resources/dbscripts/cdm/mysql.sql
+++ b/features/device-mgt/io.entgra.device.mgt.core.device.mgt.basics.feature/src/main/resources/dbscripts/cdm/mysql.sql
@@ -133,7 +133,7 @@ CREATE TABLE IF NOT EXISTS DM_ENROLMENT (
     DM_DEVICE (ID) ON DELETE NO ACTION ON UPDATE NO ACTION
 )ENGINE = InnoDB;
 CREATE INDEX IDX_ENROLMENT_FK_DEVICE_ID ON DM_ENROLMENT(DEVICE_ID);
-CREATE INDEX IDX_ENROLMENT_DEVICE_TYPE_ID ON DM_ENROLMENT(DEVICE_TYPE_ID);
+CREATE INDEX IDX_ENROLMENT_DEVICE_TYPE ON DM_ENROLMENT(DEVICE_TYPE);
 CREATE INDEX IDX_ENROLMENT_DEVICE_IDENTIFICATION ON DM_ENROLMENT(DEVICE_IDENTIFICATION);
 CREATE INDEX IDX_ENROLMENT_STATUS ON DM_ENROLMENT(STATUS);