How do we transmit values between pages? Solution

How do we transmit values between pages? 1) for example, if a member $ member_no comes in, how can this value be obtained on each page? 2) how can we simplify the process of connecting pages to a database without having to write database connection statements on every page ?, Are you a beginner? You can use $ _ SESSION or COOKIE to set global variables. how can a value be transferred between pages?
1) for example, if a member $ member_no comes in, how can this value be obtained on each page?
2) how can we simplify the process of connecting pages to a database without having to write database connection statements on every page?


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Are you a beginner?
You can use $ _ SESSION or COOKIE to set global variables.
If needed, you can even use memcache or redis

Generally, write a Database link code in conn. php, and include the file as needed. of course, you can even use a long link...


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Well, write a database connection file, conn. php. how can I import the file at the top of the page for accessing the database?