Update section of the BLOB column having both XML and encrypted data

User_QH2BL

I have a BLOB column which start with encrypted data and then XML tags in English text. XML Tag always start with tags and always ends with and after that, we have another set of encrypted data.

We are not bothered about encrypted data, I want to update the complete XML content in this column starting from safetytable tag and ending with safetytable tag and replace it with another block of XML data example below without touching encrypted data.

I tried with the REPLACE function but it is not updating the data. Below is just the sample column data I gave. In actuality, I have XML data with huge chunk of XML File to be replaced.

BLOB Before update:

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  <safetytable>
  <safetytableid>E3223</safetytableid> 
  <transmissiondater>20201007105128-0700</transmissiondater> 
  <tabletype>2</tabletype> 
  </safetytable>"
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BLOB after update:

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<safetytable>
  <safetytableid>E322w2</safetytableid> 
  <transmissiondater>20201007105128-0700</transmissiondater> 
  <tabletype>1</tabletype> 
   <newelement1>3399494</newelement>
  <newelement2>009939</newelement>
    </safetytable>
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