Oracle 18c

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CREATE TABLE EVENT
   (    
    "ID" NUMBER(19,0) NOT NULL ENABLE, 
    "CREATED" TIMESTAMP (6) NOT NULL, 
    "CUSTOMER_ID" VARCHAR2(255 CHAR) NOT NULL, 
    "CONF_ID" VARCHAR2(255 CHAR), 
    "STATE" VARCHAR2(255 CHAR) NOT NULL,
    "ITEM_ID" VARCHAR2(255 CHAR) NOT NULL
   )
INSERT INTO event 
SELECT 1, SYSTIMESTAMP, '1', '1', 'DEACTIVATED', '1' FROM DUAL UNION ALL
SELECT 1, SYSTIMESTAMP - INTERVAL '1' SECOND, '1', '1', 'ACTIVATED', '1' FROM DUAL;
2 rows affected

SELECT *
FROM   (
  SELECT customer_id,
         conf_id,
         state
  FROM   (
    SELECT customer_id,
           conf_id,
           state,
           RANK() OVER (PARTITION BY customer_id, conf_id, item_id ORDER BY created DESC) AS rnk
    FROM   event
    WHERE  state IN ('ACTIVATED', 'SUSPENDED', 'DEACTIVATED')
  )
  WHERE  rnk = 1
)
PIVOT (
  COUNT(*)
  FOR state IN (
    'ACTIVATED' AS activated,
    'SUSPENDED' AS suspended,
    'DEACTIVATED' AS deactivated
  )
);


CUSTOMER_ID
CONF_ID
ACTIVATED
SUSPENDED
DEACTIVATED


1
1
0
0
1