how to set particular column as primary key with auto increment in mysql.am using alter statement . but am getting error when i excecute the alter statement in mysql.
alter statement
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ALTER TABLE tbl_travelplan add COLUMN TRREQNO id INT(11) NOT NULL AUTO_INCREMENT, ADD PRIMARY KEY (id);
I think the real problem is the space between TRREQNO and id in your query. Try the query i have placed below:
ALTER TABLE tbl_travelplan add TRREQNO_id INT(11) NOT NULL primary KEY AUTO_INCREMENT;
You need to DROP THE PRIMARY KEY FIRST: Try this ::
ALTER TABLE tbl_travelplan add TRREQNO_id INT(11) NOT NULL AUTO_INCREMENT, DROP PRIMARY KEY,PRIMARY KEY;
ALTER TABLE tbl_travelplan add TRREQNO_id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY;
You have to drop the existing index first using
DROP_INDEX [your_existing_index] ON tbl_travelplan
You can use this query
alter table tbl_travelplan
add TRREQNO_id int(11) NOT NULL AUTO_INCREMET PRIMARY KEY
I think in that table already having primary key. So only these kind of error came. Please remove the primary key and run your query.
Please run this query
ALTER TABLE `table_name` add TRREQNO id INT(11) NOT NULL AUTO_INCREMENT DROP PRIMARY KEY ,
ADD PRIMARY KEY ( `id` )
