HOW TO REMOVE FULLTEXT INDEX FROM COLUMN IN MYSQL TABLE

for this first you check the DDL of your table
Here given the example which is based on a sample table "tbl_Company"
Run following Query to display the DDL for your table, including the system-assigned name for the index.
SHOW CREATE TABLE tbl_Company;
the resuly will look like this:
CREATE TABLE tbl_Company ( `Company_Id` int(11) NOT NULL auto_increment, `Company_Title` varchar(150) , `Company_Details` Text, PRIMARY KEY (`Company_Id`), FULLTEXT KEY `Company_Title` (`Company_Title`,`Company_Details`) ) ENGINE=MyISAM
Here in the above result , you can see that the full-text index is referred by the key name as `Company_Title`
To remove the Full-Text index You should refer the FULLTEXT KEY (from the above example it is "Company_Title" ) and the SQL statement comes like this:
ALTER TABLE `tbl_Company` DROP INDEX `Company_Title`;
OR
DROP INDEX `Company_Title` ON `tbl_Company`
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