如何比較具有相同結構的兩個表中的列值，然后選擇具有不同值的列

Question

我有兩個表，vessel_details和vessel_history。 這兩個表具有相同的字段。 我必須比較所有字段的值，並選擇具有不同值且不為null的列。 例如，ship_name字段，我必須檢查vessel_details表中的ship_name字段的值是否與vessel_history表中的ship_name不同。 如果值不同且不為null，則必須從vessel_history中選擇並顯示該值。

對正確的查詢有什么想法嗎？ 謝謝。

Answer 1

SELECT vessel_details.<your_id>, 'Difference in Column ship_name for ship_name = ' + vessel_history.ship_name 
FROM vessel_details
JOIN vessel_history ON vessel_details.<your_id> ON vessel_history.<id_from_vessel_details>
WHERE vessel_details.ship_name <> vessel_history.ship_name

UNION

SELECT vessel_details.<your_id>, 'Difference in Column ship_model for ship_model = ' + vessel_history.ship_model 
FROM vessel_details
JOIN vessel_history ON vessel_details.<your_id> ON vessel_history.<id_from_vessel_details>
WHERE vessel_details.ship_model <> vessel_history.ship_model

.
.
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對要檢查的所有列，依此類推。

您正在尋找什么？

每個項目編輯一行：

SELECT vessel_details.<your_id>,
CASE WHEN vessel_details.ship_name <> vessel_history.ship_name THEN Convert(bit, 1) ELSE Convert(bit, 0) END AS ship_name_different,
CASE WHEN vessel_details.ship_model <> vessel_history.ship_model THEN Convert(bit, 1) ELSE Convert(bit, 0) END AS ship_model_different
FROM vessel_details
JOIN vessel_history ON vessel_details.<your_id> ON vessel_history.<id_from_vessel_details>
WHERE vessel_details.ship_name <> vessel_history.ship_name 
OR vessel_details.ship_model <> vessel_history.ship_model