# Comparison with Self-built Databases 

<table>
    <tr>
        <td>Comparison Item</td>
        <td>UDB-MySQL</td>
        <td>UHost Self-built</td>
        <td>Self-built Database</td>
    </tr>
    <tr>
        <td rowspan="3">Cost Performance</td>
        <td>Elastic Resources</td>
        <td>Elastic Resources</td>
        <td>Large sunk cost for one-time investment</td>
    </tr>
    <tr>
        <td>Kernel tuning to improve performance</td>
        <td>No performance optimization for open source version</td>
        <td>No performance optimization for open source version</td>
    </tr>
    <tr>
        <td>Free backup space</td>
        <td>Need to purchase resources for backup space</td>
        <td>Need to separately prepare backup resources, with extremely high costs</td>
    </tr>
    <tr>
        <td rowspan="2">Availability</td>
        <td>High-availability version provides dual-master hot backup architecture, achieving about 20-seconds failure recovery</td>
         <td>Need to purchase a high-availability system separately</td>
         <td>Need to purchase a high-availability system separately</td>
    </tr>
    <tr>
        <td>Cloud platform enables read-write separation with one click to achieve load balancing, convenient to use</td>
        <td>Need to implement load balancing separately</td>
        <td>Need to implement load balancing equipment separately</td>
    </tr>
    <tr>
        <td rowspan="1">Reliability</td>
        <td>High data reliability, supports physical backup and logical backup, backup recovery, and seconds-level rollback, etc.</td>
        <td>High reliability can be achieved under good architecture</td>
        <td>Average data reliability, depending on the damage probability of single disk</td>
    </tr>
    <tr>
        <td rowspan="3">Ease of Use</td>
        <td>Automated backup recovery system, supports point-in-time recovery, etc.</td>
         <td>No automatic backup system, the implementation of streaming backup capability and point-in-time recovery function are costly</td>
         <td>No automatic backup system, the implementation of streaming backup capability and point-in-time recovery function are costly</td>
    </tr>
    <tr>
        <td>Automated monitoring alarm system, supports second-level monitoring, covers all performance indicators of instances and databases, supports SMS, email, etc.</td>
        <td>Need to separately purchase a monitoring system and set up alarm system in cloud monitoring</td>
        <td>Need to separately purchase or set up a monitoring system, fewer channels available, with higher cost</td>
    </tr>
     <tr>
        <td>Supports cross-availability zone disaster recovery</td>
        <td>Implementation is technically difficult</td>
        <td>Establishing cross-availability zone data centers is extremely costly, technically challenging, making it difficult to achieve cross-availability zone disaster recovery</td>
    </tr>
    <tr>
        <td rowspan="3">Performance</td>
        <td>NVMe-model MySQL delivers superior performance, extremely cost-effective</td>
         <td>Local disks equals to lower data reliability, if adopting cloud disks, architecture planning is needed and the costs are higher</td>
         <td>Generally lower than cloud database in performance as hardware update speed is slower than cloud computing</td>
    </tr>
    <tr>
        <td>Performance is robust and load balanced after adding read-only instances</td>
        <td>It's challenging to implement master+slave architecture, resulting in high consulting cost and maintenance cost</td>
        <td>It's challenging to implement master+slave architecture, resulting in high consulting cost and maintenance cost</td>
    </tr>
     <tr>
        <td>Provides a wealth of monitoring indicators, meeting most monitoring and performance optimization database scenarios</td>
        <td>Relies on senior DBAs, which is expensive and restricted people</td>
        <td>Relies on senior DBAs, which is expensive and restricted people</td>
    </tr>
    <tr>
        <td rowspan="2">Security</td>
        <td>Intranet isolation controls access, VPC network isolation</td>
         <td>VPC network isolation</td>
         <td>Network isolation consulting cost is high</td>
    </tr>
    <tr>
        <td>Supports database auditing</td>
        <td>Auditing is difficult, need to save SQL logs separately</td>
        <td>Auditing is difficult, need to save SQL logs separately</td>
    </tr>
</table>