[SQL ] 請問這兩個語法結果一樣嗎？
資料庫名稱：MySQL
內容/問題描述：您好我是初學者，想知道下面兩個語法的結果是一樣的嗎？
謝謝！
SELECT COUNT(DISTINCT pid) AS Hispanic
FROM (SELECT patients.pid, patients.ethnicity, ethnicity.Name, ethnicity.Code
FROM ethnicity
INNER JOIN patients
ON patients.ethnicity=ethnicity.Code)
WHERE Name='Hispanic or Latino';
SELECT COUNT(DISTINCT patients.pid) AS Hispanic
FROM ethnicity, patients
WHERE patients.ethnicity=ethnicity.Code
AND ethnicity.Name='Hispanic or Latino';
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