Isnumeric function?

<p><font size="2">How could you determine if a value being inserted into a varchar column is numeric?</font><p><font
size="2">Iwas thinking of using a Regular expression to find this, something like</font><p><font size="2">.. Where
content~* '^[0-9]{1,10}'</font><p><font size="2">There must be an easier way like a isNumeric()
function?</font><p><fontsize="2">Theo</font><table><tr><td bgcolor="#ffffff"><font
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