Oracle中的PL / SQL从CLOB JSON值中提取数据

Question

我希望在Oracle中使用PL / SQL进行以下语句 我在oracle DB中有2个表     

    <table>
      <tr>
        <th>Value1</th>
        <th>value2</th>
        <th>Value3</th>
      </tr>
      <tr>
        <td>xxx</td>
        <td>ppp</td>
        <td>hello</td>
      </tr>
      <tr>
        <td>yyy</td>
        <td>qqq</td>
        <td>hello1</td>
      </tr></table>

表2

 <tr>
    <th>Id</th>
    <th>Msg</th>
   
  </tr>
  <tr>
    <td>1</td>
    <td>  {
    "messages": [
        {
            "source": "abc",
            "messageType": "pqr"
        },
        {
            "source": "abc",
            "messageType": "pqr"
        }
    ],
    "value1": "xxx",
    "value2": "ppp"
}
</td>
    
  </tr>
  

我应该根据table2中的value1或value2得到值“hello”或“hello1”