Must an extra value be provided on DATA statement?

[SMcNeill]

No, it is not necessary to add a superfluous value to the DATA statement.
It is sufficient to add a not-really-superfluous comma after the last item to be read.

'instead of 
'mydata: Data 8,1,2,3,4,5,6,7,8,9999
'use:
mydata: Data 8,1,2,3,4,5,6,7,8,9999,

The QB64PE documentation page syntax diagram for the DATA statement clearly shows that every value is followed by a comma:

DATA [value1, value2, …]

Kindly look at the samples for the wiki page.

And then remember to look at this highlight from the description:

Comments after a data line require a colon before the comment.


Also notice the example on the wiki page:

Code: (Select All)

Restore Database2

Read A$, B$, C$, D$ 'read 4 string values from second DATA field

Print A$ + B$ + C$ + D$ 'note that quoted strings values are spaced



Restore Database1

For i = 1 To 18

    Read number% 'read first DATA field 18 times only

    Print number%;

Next



End



Database1:

Data 1,0,0,1,1,0,1,1,1

Data 2,0,0,2,2,0,2,2,2: ' DATA line comments require a colon



Database2:

Data "Hello, ","world! ",Goodbye,work!

The issue isn't any need to end DATA with a comma. That's not required at all.
The issue is reading a STRING as a NUMBER and blipping an error attempting it.