如果行匹配，如何比较来自不同表的两行并显示表值？

Question

I have two different tables. One is person and the other one is Cardholder . Both of these tables have one row with the similar name and same value and its called personId . What I am trying to do is compare the row personId on the person table to personId on the Cardholder table and print only rows that match the value of personId on both tables. How would I write in PHP to do such task? I tried few things but failed to do what I intend.

Answer 1

The sql query would look something like this :

SELECT P.* FROM person P INNER JOIN Cardholder C ON C.personId=P.personId

this would only select the fields from the table person that has a match on personId in the Cardholder table.

Answer 2

You will need code like this one

MySQL Code: -

("SELECT Cardholder.personId, person.personId FROM Cardholder INNER JOIN person ON Cardholder.personId = person.personId");

PHP Code: -

if (count($SQLstatment) > 0) {Exist} else {Not}