mysql问题与删除记录

Question

I have a web page with a grid of row and columns and I need to keep track of activity that happens in a given cell. Items can be moved around between cells so I keep a record in a MySQL table to track the contents of each cell. The key to the db record is row number and column number, for example, the key to the record representing row 2, column 7 is r2c7.

When an item gets put into r2c7, I insert a record with r2c7 as the key field value. If the contents of r2c7 gets move to r3c8, I insert a record into r3c8 and delete the record for r2c7. All is fine up to this point.

What I am finding though, is that after I've deleted a record for a cell, say r2c7, if I then try to re-insert the same record back in for r2c7, the insert does not stick, even though MySQL reports success on the insert. To be clear, all fields in the record that I previously deleted, are the same when I go to re-insert. It seems the database sees a duplicate record trying to be re-inserted and does not process it, even though success is reported.

Anyone have an idea of what is going on?

Answer 1

Check mysqli_affected_rows($con) ; It will definitely gives you a false as return if the row insert was unsuccessfull