How to get auto increment value to start from highest number in column?

Question

I am migrating a site from Joomla 1.5 to Joomla 3.5x. The old site used the JoomlaTags component, which is no longer available. I have successfully mapped the tables from old to new, and I can import them into the contentitem_tag_map table and it worked great.

The problem is, any new content items that are assigned tags do not auto increment from the highest core_content_id colum value in that column, which results in duplicated values in that column, which in turn causes a compact list of tags to duplicate titles when it shouldn't. for example:

Content item #3 uses Core Content ID 6 and Tag ID 17

Content item #1316 was created last and assigned Core Content ID 6 due to auto increment (the highest number in the column is 720).

Two different articles using the same tag and Core Content ID results in the two articles sharing the title, although they are different articles.

Is there a way to alter the db or code so that it auto increments based on the highest number in the core_content_id column?

Answer 1

You can set the AUTO_INCREMENT via a direct sql query.

e.g.

ALTER TABLE `tableName` AUTO_INCREMENT=100

So you could use the MAX() function to get the value of the auto increment column as a sub-query if you needed to automate it.