How to display html content stored in database into json formatted output
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I am writing a web service to output data in `json format`. 
The data stored in database contains html tags,elements,special characters etc.

Firstly,
I wrote a sql query to find what data should be printed in web service. Its working fine but when i display the content it is showing `NULL` . But data exists in database. I am not understanding why this is happening . 
please help