Get last created ID with auto-increment in MySQL

I have a primary index on column URL but at the same time I need to have records with URL left blank which won't be permitted by the index.

I thought of a solution which is to add a new column called ID and make it auto-increment.

So I need to get the ID created with auto-increment on INSERT so that I stick it to column URL too. How can I do this?

If you can think of a bette开发者_JAVA技巧r solution please tell

thanks

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It is almost certainly better to use the mysql wrapper in your scripting language of choice to acquire the last insert id, but you can SELECT LAST_INSERT_ID(); to get it with mysql itself.

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The solution may depend on what other columns you have on your table. It will be hard for you to add an auto_increment column to a table that already has data. The process will be to create a new table with the new column added and add the data from the old table and then drop the old table and re-name the new one to the matching name.