title: How to Validate data is Hexadecimal or not in Oracle
body: <p>I have a table tbl_1 with fields fl_1 (varchar2 type), contain Hexadecimal format. Now i want validate (query) where is in Hexa format and where is not.</p>
  
  <p>any idea in oracle script (SQL Syntax)?</p>
  
  <pre><code>CREATE TABLE TBL_1 (HEX VARCHAR2(20));
  INSERT INTO TBL_1 VALUES('9851010A'); 
  INSERT INTO TBL_1 VALUES('9851010B'); 
  INSERT INTO TBL_1 VALUES('FIRDI2'); 
  INSERT INTO TBL_1 VALUES('FIRDI'); 
  commit;
  </code></pre>
  
  <p>should only value 'FIRDI' AND 'FIRDI2' are false.</p>