diff --git a/database/db.changelog-3.0.xml b/database/changelog-3.3.xml
similarity index 60%
rename from database/db.changelog-3.0.xml
rename to database/changelog-3.3.xml
index 453f6f00b..25b359401 100644
--- a/database/db.changelog-3.0.xml
+++ b/database/changelog-3.3.xml
@@ -5,28 +5,28 @@
   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
                       http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
 
-  <changeSet author="author" id="changelog-3.0">
+  <changeSet author="author" id="changelog-3.3">
 
     <preConditions onFail="MARK_RAN">
       <not>
-        <tableExists tableName="traccar" />
+        <tableExists tableName="server" />
       </not>
     </preConditions>
 
-    <createTable tableName="user">
+    <createTable tableName="users">
       <column name="id" type="INT" autoIncrement="true">
         <constraints primaryKey="true" />
       </column>
-      <column name="name" type="VARCHAR(1024)">
+      <column name="name" type="VARCHAR(128)">
         <constraints nullable="false" />
       </column>
-      <column name="email" type="VARCHAR(256)">
+      <column name="email" type="VARCHAR(128)">
         <constraints nullable="false" />
       </column>
-      <column name="hashedPassword" type="VARCHAR(1024)">
+      <column name="hashedPassword" type="VARCHAR(128)">
         <constraints nullable="false" />
       </column>
-      <column name="salt" type="VARCHAR(1024)" defaultValue="">
+      <column name="salt" type="VARCHAR(128)">
         <constraints nullable="false" />
       </column>
       <column name="readonly" type="BOOLEAN" defaultValueBoolean="false">
@@ -35,16 +35,16 @@
       <column name="admin" type="BOOLEAN" defaultValueBoolean="false">
         <constraints nullable="false" />
       </column>
-      <column name="map" type="VARCHAR(1024)" defaultValue="osm">
+      <column name="map" type="VARCHAR(128)" defaultValue="osm">
         <constraints nullable="false" />
       </column>
-      <column name="language" type="VARCHAR(1024)" defaultValue="en">
+      <column name="language" type="VARCHAR(128)" defaultValue="en">
         <constraints nullable="false" />
       </column>
-      <column name="distanceUnit" type="VARCHAR(1024)" defaultValue="km">
+      <column name="distanceUnit" type="VARCHAR(128)" defaultValue="km">
         <constraints nullable="false" />
       </column>
-      <column name="speedUnit" type="VARCHAR(1024)" defaultValue="kmh">
+      <column name="speedUnit" type="VARCHAR(128)" defaultValue="kmh">
         <constraints nullable="false" />
       </column>
       <column name="latitude" type="DOUBLE" defaultValueNumeric="0">
@@ -58,25 +58,24 @@
       </column>
     </createTable>
 
-    <addUniqueConstraint tableName="user" columnNames="email" constraintName="uk_user_email" />
+    <addUniqueConstraint tableName="users" columnNames="email" constraintName="uk_user_email" />
 
-    <createTable tableName="device">
+    <createTable tableName="devices">
       <column name="id" type="INT" autoIncrement="true">
         <constraints primaryKey="true" />
       </column>
-      <column name="name" type="VARCHAR(1024)">
+      <column name="name" type="VARCHAR(128)">
         <constraints nullable="false" />
       </column>
-      <column name="uniqueId" type="VARCHAR(256)">
+      <column name="uniqueId" type="VARCHAR(128)">
         <constraints nullable="false" />
       </column>
-      <column name="status" type="VARCHAR(1024)" />
+      <column name="status" type="VARCHAR(128)" />
       <column name="lastUpdate" type="TIMESTAMP" />
       <column name="positionId" type="INT" />
-      <column name="dataId" type="INT" />
     </createTable>
 
-    <addUniqueConstraint tableName="device" columnNames="uniqueId" constraintName="uk_device_uniqueId" />
+    <addUniqueConstraint tableName="devices" columnNames="uniqueId" constraintName="uk_device_uniqueId" />
 
     <createTable tableName="user_device">
       <column name="userId" type="INT">
@@ -85,26 +84,20 @@
       <column name="deviceId" type="INT">
         <constraints nullable="false" />
       </column>
-      <column name="read" type="BOOLEAN" defaultValueBoolean="true">
-        <constraints nullable="false" />
-      </column>
-      <column name="write" type="BOOLEAN" defaultValueBoolean="true">
-        <constraints nullable="false" />
-      </column>
     </createTable>
 
-    <addForeignKeyConstraint baseTableName="user_device" baseColumnNames="userId" constraintName="fk_user_device_userId" referencedTableName="user" referencedColumnNames="id" onDelete="CASCADE" />
-    <addForeignKeyConstraint baseTableName="user_device" baseColumnNames="deviceId" constraintName="fk_user_device_deviceId" referencedTableName="device" referencedColumnNames="id" onDelete="CASCADE" />
+    <addForeignKeyConstraint baseTableName="user_device" baseColumnNames="userId" constraintName="fk_user_device_userId" referencedTableName="users" referencedColumnNames="id" onDelete="CASCADE" />
+    <addForeignKeyConstraint baseTableName="user_device" baseColumnNames="deviceId" constraintName="fk_user_device_deviceId" referencedTableName="devices" referencedColumnNames="id" onDelete="CASCADE" />
 
     <createIndex tableName="user_device" indexName="user_device_user_id">
       <column name="userId" />
     </createIndex>
 
-    <createTable tableName="position">
+    <createTable tableName="positions">
       <column name="id" type="INT" autoIncrement="true">
         <constraints primaryKey="true" />
       </column>
-      <column name="protocol" type="VARCHAR(1024)" />
+      <column name="protocol" type="VARCHAR(128)" />
       <column name="deviceId" type="int">
         <constraints nullable="false" />
       </column>
@@ -126,65 +119,52 @@
       <column name="longitude" type="DOUBLE">
         <constraints nullable="false" />
       </column>
-      <column name="altitude" type="DOUBLE">
+      <column name="altitude" type="FLOAT">
         <constraints nullable="false" />
       </column>
-      <column name="speed" type="DOUBLE">
+      <column name="speed" type="FLOAT">
         <constraints nullable="false" />
       </column>
-      <column name="course" type="DOUBLE">
+      <column name="course" type="FLOAT">
         <constraints nullable="false" />
       </column>
-      <column name="address" type="VARCHAR(1024)" />
-      <column name="other" type="VARCHAR(8192)">
+      <column name="address" type="VARCHAR(512)" />
+      <column name="attributes" type="VARCHAR(4096)">
         <constraints nullable="false" />
       </column>
     </createTable>
 
-    <addForeignKeyConstraint baseTableName="position" baseColumnNames="deviceId" constraintName="fk_position_deviceId" referencedTableName="device" referencedColumnNames="id" onDelete="CASCADE" />
+    <addForeignKeyConstraint baseTableName="positions" baseColumnNames="deviceId" constraintName="fk_position_deviceId" referencedTableName="devices" referencedColumnNames="id" onDelete="CASCADE" />
 
-    <createTable tableName="data">
-      <column name="id" type="INT" autoIncrement="true">
-        <constraints primaryKey="true" />
-      </column>
-      <column name="protocol" type="VARCHAR(1024)" />
-      <column name="deviceId" type="int">
-        <constraints nullable="false" />
-      </column>
-      <column name="serverTime" type="TIMESTAMP">
-        <constraints nullable="false" />
-      </column>
-      <column name="deviceTime" type="TIMESTAMP">
-        <constraints nullable="false" />
-      </column>
-      <column name="other" type="VARCHAR(8192)">
-        <constraints nullable="false" />
-      </column>
-    </createTable>
-
-    <addForeignKeyConstraint baseTableName="data" baseColumnNames="deviceId" constraintName="fk_data_deviceId" referencedTableName="device" referencedColumnNames="id" onDelete="CASCADE" />
+    <createIndex tableName="positions" indexName="position_deviceId_fixTime">
+      <column name="deviceId" />
+      <column name="fixTime" />
+    </createIndex>
 
     <createTable tableName="server">
       <column name="id" type="INT" autoIncrement="true">
         <constraints primaryKey="true" />
       </column>
-      <column name="registration" type="BOOLEAN">
+      <column name="registration" type="BOOLEAN" defaultValueBoolean="true">
         <constraints nullable="false" />
       </column>
-      <column name="latitude" type="DOUBLE">
+      <column name="latitude" type="DOUBLE" defaultValueNumeric="0">
         <constraints nullable="false" />
       </column>
-      <column name="longitude" type="DOUBLE">
+      <column name="longitude" type="DOUBLE" defaultValueNumeric="0">
         <constraints nullable="false" />
       </column>
-      <column name="zoom" type="INT">
+      <column name="zoom" type="INT" defaultValueNumeric="0">
         <constraints nullable="false" />
       </column>
-    </createTable>
-
-    <createTable tableName="traccar">
-      <column name="id" type="INT" autoIncrement="true">
-        <constraints primaryKey="true" />
+      <column name="map" type="VARCHAR(128)" />
+      <column name="language" type="VARCHAR(128)" />
+      <column name="distanceUnit" type="VARCHAR(128)" />
+      <column name="speedUnit" type="VARCHAR(128)" />
+      <column name="bingKey" type="VARCHAR(128)" />
+      <column name="mapUrl" type="VARCHAR(128)" />
+      <column name="readonly" type="BOOLEAN" defaultValueBoolean="false">
+        <constraints nullable="false" />
       </column>
     </createTable>
 
@@ -195,7 +175,7 @@
       <column name="zoom" valueNumeric="0" />
     </insert>
 
-    <insert tableName="user">
+    <insert tableName="users">
       <column name="name" value="admin" />
       <column name="email" value="admin" />
       <column name="hashedPassword" value="D33DCA55ABD4CC5BC76F2BC0B4E603FE2C6F61F4C1EF2D47" />
diff --git a/database/changelog-master.xml b/database/changelog-master.xml
new file mode 100644
index 000000000..595643dce
--- /dev/null
+++ b/database/changelog-master.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?> 
+<databaseChangeLog
+  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
+                      http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
+
+  <include file="changelog-3.3.xml" relativeToChangelogFile="true" />
+</databaseChangeLog>
diff --git a/database/db.changelog-3.1.xml b/database/db.changelog-3.1.xml
deleted file mode 100644
index 740da4e2f..000000000
--- a/database/db.changelog-3.1.xml
+++ /dev/null
@@ -1,131 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<databaseChangeLog
-  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
-  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
-                      http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
-
-  <changeSet author="author" id="changelog-3.1">
-
-    <preConditions onFail="MARK_RAN">
-      <not>
-        <columnExists tableName="traccar" columnName="version" />
-      </not>
-    </preConditions>
-
-    <dropNotNullConstraint tableName="user" columnName="name" columnDataType="VARCHAR(1024)" />
-    <modifyDataType tableName="user" columnName="name" newDataType="VARCHAR(128)" />
-    <addNotNullConstraint tableName="user" columnName="name" columnDataType="VARCHAR(128)" />
-    <dropUniqueConstraint tableName="user" uniqueColumns="email" constraintName="uk_user_email" />
-    <dropNotNullConstraint tableName="user" columnName="email" columnDataType="VARCHAR(256)" />
-    <modifyDataType tableName="user" columnName="email" newDataType="VARCHAR(128)" />
-    <addNotNullConstraint tableName="user" columnName="email" columnDataType="VARCHAR(128)" />
-    <addUniqueConstraint tableName="user" columnNames="email" constraintName="uk_user_email" />
-    <dropNotNullConstraint tableName="user" columnName="hashedPassword" columnDataType="VARCHAR(1024)" />
-    <modifyDataType tableName="user" columnName="hashedPassword" newDataType="VARCHAR(128)" />
-    <addNotNullConstraint tableName="user" columnName="hashedPassword" columnDataType="VARCHAR(128)" />
-    <dropDefaultValue tableName="user" columnName="salt" />
-    <dropNotNullConstraint tableName="user" columnName="salt" columnDataType="VARCHAR(1024)" />
-    <modifyDataType tableName="user" columnName="salt" newDataType="VARCHAR(128)" />
-    <addNotNullConstraint tableName="user" columnName="salt" columnDataType="VARCHAR(128)" />
-    <addDefaultValue tableName="user" columnName="salt" defaultValue="" />
-    <dropDefaultValue tableName="user" columnName="map" />
-    <dropNotNullConstraint tableName="user" columnName="map" columnDataType="VARCHAR(128)" />
-    <modifyDataType tableName="user" columnName="map" newDataType="VARCHAR(128)" />
-    <dropDefaultValue tableName="user" columnName="language" />
-    <dropNotNullConstraint tableName="user" columnName="language" columnDataType="VARCHAR(128)" />
-    <modifyDataType tableName="user" columnName="language" newDataType="VARCHAR(128)" />
-    <dropDefaultValue tableName="user" columnName="distanceUnit" />
-    <dropNotNullConstraint tableName="user" columnName="distanceUnit" columnDataType="VARCHAR(128)" />
-    <modifyDataType tableName="user" columnName="distanceUnit" newDataType="VARCHAR(128)" />
-    <dropDefaultValue tableName="user" columnName="speedUnit" />
-    <dropNotNullConstraint tableName="user" columnName="speedUnit" columnDataType="VARCHAR(128)" />
-    <modifyDataType tableName="user" columnName="speedUnit" newDataType="VARCHAR(128)" />
-    <dropDefaultValue tableName="user" columnName="latitude" />
-    <dropNotNullConstraint tableName="user" columnName="latitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="user" columnName="latitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="user" columnName="latitude" columnDataType="FLOAT" />
-    <addDefaultValue tableName="user" columnName="latitude" defaultValueNumeric="0" />
-    <dropDefaultValue tableName="user" columnName="longitude" />
-    <dropNotNullConstraint tableName="user" columnName="longitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="user" columnName="longitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="user" columnName="longitude" columnDataType="FLOAT" />
-    <addDefaultValue tableName="user" columnName="longitude" defaultValueNumeric="0" />
-
-    <dropNotNullConstraint tableName="device" columnName="name" columnDataType="VARCHAR(1024)" />
-    <modifyDataType tableName="device" columnName="name" newDataType="VARCHAR(128)" />
-    <addNotNullConstraint tableName="device" columnName="name" columnDataType="VARCHAR(128)" />
-    <dropUniqueConstraint tableName="device" uniqueColumns="uniqueId" constraintName="uk_device_uniqueId" />
-    <dropNotNullConstraint tableName="device" columnName="uniqueId" columnDataType="VARCHAR(256)" />
-    <modifyDataType tableName="device" columnName="uniqueId" newDataType="VARCHAR(128)" />
-    <addNotNullConstraint tableName="device" columnName="uniqueId" columnDataType="VARCHAR(128)" />
-    <addUniqueConstraint tableName="device" columnNames="uniqueId" constraintName="uk_device_uniqueId" />
-    <modifyDataType tableName="device" columnName="status" newDataType="VARCHAR(128)" />
-
-    <modifyDataType tableName="position" columnName="protocol" newDataType="VARCHAR(128)" />
-    <dropNotNullConstraint tableName="position" columnName="latitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="position" columnName="latitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="position" columnName="latitude" columnDataType="FLOAT" />
-    <dropNotNullConstraint tableName="position" columnName="longitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="position" columnName="longitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="position" columnName="longitude" columnDataType="FLOAT" />
-    <dropNotNullConstraint tableName="position" columnName="altitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="position" columnName="altitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="position" columnName="altitude" columnDataType="FLOAT" />
-    <dropNotNullConstraint tableName="position" columnName="speed" columnDataType="DOUBLE" />
-    <modifyDataType tableName="position" columnName="speed" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="position" columnName="speed" columnDataType="FLOAT" />
-    <dropNotNullConstraint tableName="position" columnName="course" columnDataType="DOUBLE" />
-    <modifyDataType tableName="position" columnName="course" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="position" columnName="course" columnDataType="FLOAT" />
-    <modifyDataType tableName="position" columnName="address" newDataType="VARCHAR(512)" />
-    <dropNotNullConstraint tableName="position" columnName="other" columnDataType="VARCHAR(8192)" />
-    <modifyDataType tableName="position" columnName="other" newDataType="VARCHAR(4096)" />
-    <addNotNullConstraint tableName="position" columnName="other" columnDataType="VARCHAR(4096)" />
-
-    <createIndex tableName="position" indexName="position_deviceId_fixTime">
-      <column name="deviceId" />
-      <column name="fixTime" />
-    </createIndex>
-
-    <modifyDataType tableName="data" columnName="protocol" newDataType="VARCHAR(128)" />
-    <dropNotNullConstraint tableName="data" columnName="other" columnDataType="VARCHAR(8192)" />
-    <modifyDataType tableName="data" columnName="other" newDataType="VARCHAR(4096)" />
-    <addNotNullConstraint tableName="data" columnName="other" columnDataType="VARCHAR(4096)" />
-
-    <addColumn tableName="server">
-      <column name="map" type="VARCHAR(128)" />
-    </addColumn>
-    <addColumn tableName="server">
-      <column name="language" type="VARCHAR(128)" />
-    </addColumn>
-    <addColumn tableName="server">
-      <column name="distanceUnit" type="VARCHAR(128)" />
-    </addColumn>
-    <addColumn tableName="server">
-      <column name="speedUnit" type="VARCHAR(128)" />
-    </addColumn>
-    <dropNotNullConstraint tableName="server" columnName="latitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="server" columnName="latitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="server" columnName="latitude" columnDataType="FLOAT" />
-    <addDefaultValue tableName="server" columnName="latitude" defaultValueNumeric="0" />
-    <dropNotNullConstraint tableName="server" columnName="longitude" columnDataType="DOUBLE" />
-    <modifyDataType tableName="server" columnName="longitude" newDataType="FLOAT" />
-    <addNotNullConstraint tableName="server" columnName="longitude" columnDataType="FLOAT" />
-    <addDefaultValue tableName="server" columnName="longitude" defaultValueNumeric="0" />
-    <addDefaultValue tableName="server" columnName="zoom" defaultValueNumeric="0" />
-
-    <dropTable tableName="traccar" />
-
-    <createTable tableName="traccar">
-      <column name="version" type="INT" defaultValueNumeric="0">
-        <constraints nullable="false" />
-      </column>
-    </createTable>
-
-    <insert tableName="traccar">
-      <column name="version" valueNumeric="301" />
-    </insert>
-
-  </changeSet>
-</databaseChangeLog>
diff --git a/database/db.changelog-3.2.xml b/database/db.changelog-3.2.xml
deleted file mode 100644
index fdeabfb68..000000000
--- a/database/db.changelog-3.2.xml
+++ /dev/null
@@ -1,63 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<databaseChangeLog
-  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
-  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
-                      http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
-
-  <changeSet author="author" id="changelog-3.2">
-
-    <preConditions onFail="MARK_RAN">
-      <not>
-        <columnExists tableName="position" columnName="attributes" />
-      </not>
-    </preConditions>
-
-    <dropDefaultValue tableName="user" columnName="latitude" />
-    <dropNotNullConstraint tableName="user" columnName="latitude" columnDataType="FLOAT" />
-    <modifyDataType tableName="user" columnName="latitude" newDataType="DOUBLE" />
-    <addNotNullConstraint tableName="user" columnName="latitude" columnDataType="DOUBLE" />
-    <addDefaultValue tableName="user" columnName="latitude" defaultValueNumeric="0" />
-    <dropDefaultValue tableName="user" columnName="longitude" />
-    <dropNotNullConstraint tableName="user" columnName="longitude" columnDataType="FLOAT" />
-    <modifyDataType tableName="user" columnName="longitude" newDataType="DOUBLE" />
-    <addNotNullConstraint tableName="user" columnName="longitude" columnDataType="DOUBLE" />
-    <addDefaultValue tableName="user" columnName="longitude" defaultValueNumeric="0" />
-
-    <dropColumn tableName="device" columnName="dataId" />
-
-    <dropNotNullConstraint tableName="position" columnName="latitude" columnDataType="FLOAT" />
-    <modifyDataType tableName="position" columnName="latitude" newDataType="DOUBLE" />
-    <addNotNullConstraint tableName="position" columnName="latitude" columnDataType="DOUBLE" />
-    <dropNotNullConstraint tableName="position" columnName="longitude" columnDataType="FLOAT" />
-    <modifyDataType tableName="position" columnName="longitude" newDataType="DOUBLE" />
-    <addNotNullConstraint tableName="position" columnName="longitude" columnDataType="DOUBLE" />
-    <dropNotNullConstraint tableName="position" columnName="other" columnDataType="VARCHAR(4096)" />
-    <renameColumn tableName="position" oldColumnName="other" newColumnName="attributes" columnDataType="VARCHAR(4096)" />
-    <addNotNullConstraint tableName="position" columnName="attributes" columnDataType="VARCHAR(4096)" />
-
-    <dropTable tableName="data" />
-
-    <addColumn tableName="server">
-      <column name="bingKey" type="VARCHAR(128)" />
-    </addColumn>
-    <addColumn tableName="server">
-      <column name="mapUrl" type="VARCHAR(128)" />
-    </addColumn>
-    <dropDefaultValue tableName="server" columnName="latitude" />
-    <dropNotNullConstraint tableName="server" columnName="latitude" columnDataType="FLOAT" />
-    <modifyDataType tableName="server" columnName="latitude" newDataType="DOUBLE" />
-    <addNotNullConstraint tableName="server" columnName="latitude" columnDataType="DOUBLE" />
-    <addDefaultValue tableName="server" columnName="latitude" defaultValueNumeric="0" />
-    <dropDefaultValue tableName="server" columnName="longitude" />
-    <dropNotNullConstraint tableName="server" columnName="longitude" columnDataType="FLOAT" />
-    <modifyDataType tableName="server" columnName="longitude" newDataType="DOUBLE" />
-    <addNotNullConstraint tableName="server" columnName="longitude" columnDataType="DOUBLE" />
-    <addDefaultValue tableName="server" columnName="longitude" defaultValueNumeric="0" />
-
-    <update tableName="traccar">
-      <column name="version" valueNumeric="302" />
-    </update>
-
-  </changeSet>
-</databaseChangeLog>
diff --git a/database/db.changelog-3.3.xml b/database/db.changelog-3.3.xml
deleted file mode 100644
index 22fcd6f5c..000000000
--- a/database/db.changelog-3.3.xml
+++ /dev/null
@@ -1,32 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<databaseChangeLog
-  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
-  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
-                      http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
-
-  <changeSet author="author" id="changelog-3.3">
-
-    <dropDefaultValue tableName="user" columnName="salt" />
-
-    <addDefaultValue tableName="server" columnName="registration" defaultValueBoolean="true" />
-
-    <addColumn tableName="server">
-      <column name="readonly" type="BOOLEAN" defaultValueBoolean="false">
-        <constraints nullable="false" />
-      </column>
-    </addColumn>
-
-    <dropTable tableName="traccar" />
-
-    <renameTable oldTableName="user" newTableName="users" />
-    <renameTable oldTableName="device" newTableName="devices" />
-    <renameTable oldTableName="position" newTableName="positions" />
-
-    <dropDefaultValue tableName="user_device" columnName="read" />
-    <dropColumn tableName="user_device" columnName="read" />
-    <dropDefaultValue tableName="user_device" columnName="write" />
-    <dropColumn tableName="user_device" columnName="write" />
-
-  </changeSet>
-</databaseChangeLog>
diff --git a/database/db.changelog-master.xml b/database/db.changelog-master.xml
deleted file mode 100644
index 06fc7a695..000000000
--- a/database/db.changelog-master.xml
+++ /dev/null
@@ -1,13 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?> 
-<databaseChangeLog
-  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
-  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
-                      http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
-
-  <include file="db.changelog-normalize.xml" relativeToChangelogFile="true" />
-  <include file="db.changelog-3.0.xml" relativeToChangelogFile="true" />
-  <include file="db.changelog-3.1.xml" relativeToChangelogFile="true" />
-  <include file="db.changelog-3.2.xml" relativeToChangelogFile="true" />
-  <include file="db.changelog-3.3.xml" relativeToChangelogFile="true" />
-</databaseChangeLog>
diff --git a/database/db.changelog-normalize.xml b/database/db.changelog-normalize.xml
deleted file mode 100644
index 7621846ca..000000000
--- a/database/db.changelog-normalize.xml
+++ /dev/null
@@ -1,114 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<databaseChangeLog
-  xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
-  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
-                      http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.4.xsd">
-
-  <changeSet author="author" id="changelog-normalize-user">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-      <not>
-        <columnExists tableName="user" columnName="id"/>
-      </not>
-    </preConditions>
-
-    <renameTable oldTableName="quotedUser" newTableName="user" />
-
-    <modifySql>
-      <replace replace="quotedUser" with="&quot;user&quot;" />
-    </modifySql>
-
-  </changeSet>
-
-  <changeSet author="author" id="changelog-normalize-user-device">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-      <not>
-        <columnExists tableName="user_device" columnName="read"/>
-      </not>
-    </preConditions>
-
-    <renameColumn tableName="user_device" oldColumnName="quotedRead" newColumnName="read" columnDataType="BOOLEAN" />
-    <renameColumn tableName="user_device" oldColumnName="quotedWrite" newColumnName="write" columnDataType="BOOLEAN" />
-
-    <modifySql>
-      <replace replace="quotedRead" with="&quot;read&quot;" />
-      <replace replace="quotedWrite" with="&quot;write&quot;" />
-    </modifySql>
-
-  </changeSet>
-
-  <changeSet author="author" id="changelog-normalize-fk-h2">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-      <dbms type="h2" />
-    </preConditions>
-
-    <sql>CREATE ALIAS IF NOT EXISTS EXECUTE AS $$ void executeSql(Connection conn, String sql) throws SQLException { try { conn.createStatement().executeUpdate(sql); } catch (Exception e) {} } $$;</sql>
-
-    <sql>CALL EXECUTE('ALTER TABLE POSITION DROP CONSTRAINT ' || (SELECT DISTINCT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.CONSTRAINTS WHERE CONSTRAINT_TYPE = 'REFERENTIAL' AND TABLE_NAME = 'POSITION' AND COLUMN_LIST = 'DEVICEID'));</sql>
-    <sql>CALL EXECUTE('ALTER TABLE DEVICE DROP CONSTRAINT ' || (SELECT DISTINCT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.CONSTRAINTS WHERE CONSTRAINT_TYPE = 'REFERENTIAL' AND TABLE_NAME = 'DEVICE' AND COLUMN_LIST = 'POSITIONID'));</sql>
-    <sql>CALL EXECUTE('ALTER TABLE DEVICE DROP CONSTRAINT ' || (SELECT DISTINCT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.CONSTRAINTS WHERE CONSTRAINT_TYPE = 'REFERENTIAL' AND TABLE_NAME = 'DEVICE' AND COLUMN_LIST = 'DATAID'));</sql>
-    <sql>CALL EXECUTE('ALTER TABLE USER_DEVICE DROP CONSTRAINT ' || (SELECT DISTINCT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.CONSTRAINTS WHERE CONSTRAINT_TYPE = 'REFERENTIAL' AND TABLE_NAME = 'USER_DEVICE' AND COLUMN_LIST = 'USERID'));</sql>
-    <sql>CALL EXECUTE('ALTER TABLE USER_DEVICE DROP CONSTRAINT ' || (SELECT DISTINCT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.CONSTRAINTS WHERE CONSTRAINT_TYPE = 'REFERENTIAL' AND TABLE_NAME = 'USER_DEVICE' AND COLUMN_LIST = 'DEVICEID'));</sql>
-    <sql>CALL EXECUTE('ALTER TABLE DATA DROP CONSTRAINT ' || (SELECT DISTINCT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.CONSTRAINTS WHERE CONSTRAINT_TYPE = 'REFERENTIAL' AND TABLE_NAME = 'DATA' AND COLUMN_LIST = 'DEVICEID'));</sql>
-
-  </changeSet>
-
-  <changeSet author="author" id="changelog-normalize-fk-other">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-      <not>
-        <dbms type="h2" />
-      </not>
-    </preConditions>
-
-    <dropAllForeignKeyConstraints baseTableName="position" />
-    <dropAllForeignKeyConstraints baseTableName="device" />
-    <dropAllForeignKeyConstraints baseTableName="user_device" />
-
-  </changeSet>
-
-  <changeSet author="author" id="changelog-normalize-fk">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-    </preConditions>
-
-    <addForeignKeyConstraint baseTableName="user_device" baseColumnNames="userId" constraintName="fk_user_device_userId" referencedTableName="user" referencedColumnNames="id" onDelete="CASCADE" />
-    <addForeignKeyConstraint baseTableName="user_device" baseColumnNames="deviceId" constraintName="fk_user_device_deviceId" referencedTableName="device" referencedColumnNames="id" onDelete="CASCADE" />
-
-    <addForeignKeyConstraint baseTableName="position" baseColumnNames="deviceId" constraintName="fk_position_deviceId" referencedTableName="device" referencedColumnNames="id" onDelete="CASCADE" />
-
-  </changeSet>
-
-  <changeSet author="author" id="changelog-normalize-fk-data-other">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-      <tableExists tableName="data" />
-      <not>
-        <dbms type="h2" />
-      </not>
-    </preConditions>
-
-    <dropAllForeignKeyConstraints baseTableName="data" />
-
-  </changeSet>
-
-  <changeSet author="author" id="changelog-normalize-fk-data">
-
-    <preConditions onFail="MARK_RAN">
-      <tableExists tableName="traccar" />
-      <tableExists tableName="data" />
-    </preConditions>
-
-    <addForeignKeyConstraint baseTableName="data" baseColumnNames="deviceId" constraintName="fk_data_deviceId" referencedTableName="device" referencedColumnNames="id" onDelete="CASCADE" />
-
-  </changeSet>
-</databaseChangeLog>
diff --git a/debug.xml b/debug.xml
index 82600a3eb..eb2038cd5 100644
--- a/debug.xml
+++ b/debug.xml
@@ -49,7 +49,7 @@
     <entry key='database.user'>sa</entry>
     <entry key='database.password'></entry>
     <entry key='database.xml'>false</entry>
-    <entry key='database.changelog'>./database/db.changelog-master.xml</entry>
+    <entry key='database.changelog'>./database/changelog-master.xml</entry>
 
     <entry key='database.selectServers'>
         SELECT * FROM server;