In certain situations, however, TRIM() can’t do the job.
One space character commonly used in Web pages that TRIM() will not remove is thenon-breaking space.
Non-Breaking and Regular Spaces
Spaces are characters and each character is referenced by its ASCII code value.

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The ASCII code for a non-breaking space is160.
The ASCII code for aregularspace is32.
The TRIM() function can only remove spaces that have an ASCII code of 32.

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Different typestyles support different ranges of ASCII codes.
Then, the TRIM() function removes the standard spaces from the substituted string.
SUBSTITUTE() is useful for replacing anyASCII codewith any other.