Here's a couple of guesses at what you want:

/\d{0,3}/
matches:
"123"
"  123"
"123  "
"  123  "
"foo123bar"
doesn't match:
"1 2 3"

/^\s*\d{0,3}\s*$/
matches:
"123"
"  123"
"123  "
"  123  "
doesn't match:
"foo123bar"
"1 2 3"

/^\s*(?:\d\s*){0,3}$/
matches:
"123"
"  123"
"123  "
"  123  "
" 1 2 3 "
doesn't match:
"foo123bar"

In reply to Re: Pattern matching fields with variable or NULL data by ikegami
in thread Pattern matching fields with variable or NULL data by kerrya

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