This is how I do it:
UPDATE <tablename> SET <column> = SUBSTRING(<column>, PATINDEX('%[^0]%', <column>), CHAR_LENGTH(<column>)) WHERE <column> LIKE '0%'
Obviously, the most interesting part for me is the:
construct that finds the position of the first non-ZERO character in the <column> to start substring from.
For detailed info about used functions, please visit Sybase’s documentation: