Custom SQL fields - Command to add st, nd, rd or th after a day

What to use in Custom SQL field:

DATENAME(d,[Table: Field Date]) +
CASE
WHEN DATENAME(d,[Table: Field Date]) IN ('1', '21', '31') THEN 'st'
WHEN DATENAME(d,[Table: Field Date]) IN ('2', '22') THEN 'nd'
WHEN DATENAME(d,[Table: Field Date]) IN ('3', '23') THEN 'rd'
ELSE 'th'
END
+ ' ' + LEFT(DATENAME(m,[Table: Field Date]),3) + ' ' + DATENAME(yyyy,[Table: Field Date])

Example:

where [Table: Field Date] = [Assignment: Start Date]