在Big Query中比较两个连续行中的时间戳，这两个行的A列的值不同，B列的值相同

SELECT
  timestamp,
  column_A,
  column_B,
  LAG(timestamp) OVER (ORDER BY timestamp) AS previous_timestamp,
  LAG(column_A) OVER (ORDER BY timestamp) AS previous_column_A
FROM
  table_name

SELECT
  timestamp,
  column_A,
  column_B,
  previous_timestamp,
  previous_column_A
FROM (
  SELECT
    timestamp,
    column_A,
    column_B,
    LAG(timestamp) OVER (ORDER BY timestamp) AS previous_timestamp,
    LAG(column_A) OVER (ORDER BY timestamp) AS previous_column_A
  FROM
    table_name
)
WHERE
  column_A <> previous_column_A
  AND column_B = lag_column_B