Could it be that the school level field containing the values is number, not text? I just ran a test; the file sorts correctly if the field is a text field, but sorts K to last place if the field is a number field.
It is a text field, and the school level field contains values with alphanumeric (PK1, PK2...), numeric (1, 2, ....) and alphabet (K). I am sorting it according to my custom value list:
In that case I come up blank. With a text field and value list using exactly the values you specify my test file sorts exactly as expected.
As you have discovered, using mixed data in a number field does not work. For most practical purposes any alpha characters in a number field are completely ignored by FM.
If you need to use mixed data then make it a text field. However, this create an additional issue - in orfer to get numbers to sort numerically correct you have to use leading zeros with the set of single digit "numbers" because FM sees them as "text" characters and not numbers.
As a text field and with leading zero "numbers" your sort using a custom value list will work.
I've encountered the same issue before. We resulted to using a grade table and related our student records using a field called id_grade. By creating a separate, you can either:
1) create the grade records in the order that you would want to normally sort, or
2) create an additional field in the grade table where you specify a sort order (you could even call this field "sortOrder")
This is a bit of upfront work, but the payoff could end up being quite handy.
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