My oracle database version is IS 7.3.4 if i give show parameter doesnot give any information shows error message given below but samething iam able to get in ver 8.1.7

OPS3 SQL> show parameter db_block_size
unknown SHOW option "parameter"
unknown SHOW option beginning "db_block_s..."

OPS3 SQL> show sga
unknown SHOW option "sga"


OPS3 SQL> show parameter db_block_buffers
unknown SHOW option "parameter"
unknown SHOW option beginning "db_block_b..."