REPORT  z08_001                                                     .
TYPES: BEGIN OF line,
        col1,
        col2,
      END OF line.

DATA: wa TYPE line,
      itab TYPE HASHED TABLE OF line WITH UNIQUE KEY col1,
      key(4) VALUE 'COL1'.

wa-col1 = 'X'. INSERT wa INTO TABLE itab.
wa-col1 = 'Y'. INSERT wa INTO TABLE itab.

PERFORM demo USING itab.

wa-col1 = 'Z'. INSERT wa INTO TABLE itab.

FORM demo USING p TYPE ANY TABLE.
  READ TABLE p WITH TABLE KEY (key) = 'X' INTO wa.
  IF sy-subrc EQ 0.
    WRITE : / wa-col1.
  ENDIF.
ENDFORM.                    "DEMO