Reason analysis and solution of _php in PHP with self-increasing ID set example

The reason for the discontinuity of the ID setting in PHP is described as follows:

ALTER TABLE tablename drop column ID;
ALTER TABLE tablename Add ID mediumint (8) NOT null primary key auto_increment A;

Every time you delete it, add the two lines to the line.

And there's this.

Use the query () method in the Mysqli object to execute only one SQL command per call.

If you need to execute more than one SQL command at a time, you must use the Multi_query () method in the Mysqli object. The practice is to write multiple SQL commands in the same string as arguments passed to the Multi_query () method, separated by semicolons (;) between multiple SQL. This method returns true if the first SQL command does not make an error while executing, otherwise it returns false.

The above is a small series to introduce the ID set in PHP after the cause of the discontinuity and the solution, hope to be helpful to everyone, if you have any questions welcome to my message, small series will promptly reply to everyone, here also thank you for the cloud Habitat Community website support!