(PHP 3>= 3.0.6, PHP 4 >= 4.0.0)
odbc_longreadlen -- Handling of LONG columns(ODBC SQL types affected: LONG, LONGVARBINARY) The number of bytes returned to PHP is controled by the parameter length. If it is set to 0, Long column data is passed thru to the client.
Note: Handling of LONGVARBINARY columns is also affected by odbc_binmode().