MS SQL選擇的情況下查詢真的還是假的，然後執行另一個SELECT查詢

Question

嘿，我試圖找出一種方法來從下面的SQL查詢發送2結果表工作得很好。

SELECT 
    CASE WHEN EXISTS 
    (
     SELECT * FROM usersTbl WHERE name = 'Bob Barker' 
) 
    THEN 'TRUE' 
     (SELECT name FROM usersTbl WHERE name = 'Bob Barker' 
           AND active = 1) AS result2 
    ELSE 'FALSE' 
END AS result1 

|result1 | 
|---------| 
| TRUE | 

|result2  | 
|--------------| 
| Bob Barker | 

因此而不是隻RESULT1返回，這將讓雙方RESULT1和RESULT2是：如果「TRUE」這樣然而，我也需要到執行另一個select語句回。

我該如何去格式化查詢呢？

Answer 1

您查詢看起來有點不對勁......它應該是一個奇怪的一個

SELECT *, 
    CASE WHEN name = 'Bob Barker' THEN 'TRUE' ELSE 'FALSE' END AS result1 
FROM usersTbl 
WHERE name = 'Bob Barker' 
AND active = 1 

Answer 2

類，但如果你想2個的結果集，你可以使用IF EXISTS()：

IF EXISTS (SELECT * FROM usersTbl WHERE name = 'Bob Barker') 
BEGIN 
    SELECT 'TRUE' as Result1; 
    SELECT CASE WHEN EXISTS (SELECT * 
          FROM usersTbl 
          WHERE name = 'Bob Barker' 
          AND active = 1) 
       THEN (SELECT name 
         FROM usersTbl 
         WHERE name = 'Bob Barker' 
         AND active = 1) 
       ELSE 'FALSE' 
       END as Result2; 
END 

如果如果第一個結果不存在，則要返回FALSE，則必須添加另一個IF：

IF NOT EXISTS (SELECT * FROM usersTbl WHERE name = 'Bob Barker') 
BEGIN 
    SELECT 'FALSE'; 
END 

編輯：與最終FALSE全面查詢：

IF EXISTS (SELECT * FROM usersTbl WHERE name = 'Bob Barker') 
BEGIN 
    SELECT 'TRUE' as Result1; 
    SELECT CASE WHEN EXISTS (SELECT * 
          FROM usersTbl 
          WHERE name = 'Bob Barker' 
          AND active = 1) 
       THEN (SELECT name 
         FROM usersTbl 
         WHERE name = 'Bob Barker' 
         AND active = 1) 
       ELSE 'FALSE' 
       END as Result2; 
END 

IF NOT EXISTS (SELECT * FROM usersTbl WHERE name = 'Bob Barker') 
BEGIN 
    SELECT 'FALSE' as Result1; 
END 

Answer 3

這可能會爲你工作。

SELECT 
    * 
FROM subTable1 
WHERE 
    st.value = 'Value' 
    AND st.restrictiveValue = 'restrictiveValue' 
    AND (SELECT COUNT(*) AS resultCount FROM subTable1 st WHERE st.value = 'Value') != 0 

SELECT COUNT(*) AS resultCount FROM subTable1 st WHERE st.value = 'Value' 

如果你不希望它返回一個空表，你可能要考慮使用動態SQL作爲this question.