Use the str_pad function in php to generate product numbers in the incremental form

Solution: $ str = "QB". str_pad ($ maxid [0] ["max (id)"] + 1), 5, "0", STR_PAD_LEFT );

$ Maxid [0] ["max (id)"] + 1) is used to find the largest value of ID from the database using the max function. ID is the primary key and will not be repeated.

The str_pad () function fills the string with the specified length.

Syntax

Str_pad (string, length, pad_string, pad_type)

Parameters	Description
String	Required. Specifies the string to be filled.
Length	Required. Specify the length of the new string. If the value is smaller than the length of the original string, no operation is performed.
Pad_string	Optional. The specified string for filling. The default value is blank.
Pad_type	Optional. Specify the other side of the string to be filled. Possible values: STR_PAD_BOTH-fill in the two ends of the string. If it is not an even number, the right side will receive additional filling. STR_PAD_LEFT-fill in the left side of the string. STR_PAD_RIGHT-fill in the string to the right. This is the default one.