The BIT_LENGTH function returns an unsigned 64-bit value containing the bit length of the large object column or variable parameter. If the argument is NULL, BIT_LENGTH returns NULL.
BIT_LENGTH( large-object-column )
large-object-column The name of a LONG VARCHAR or LONG BINARY column or variable.
BIT_LENGTH supports all Sybase IQ data types and LONG BINARY and LONG VARCHAR variables of any size of data. Currently, a SQL variable can hold up to 2GB - 1 in length.