檢測未設置$變量在查詢TRAC報告

Question

我kludged一個TRAC報告，做這樣的事情：

SELECT status, 
    id AS ticket, summary, priority, keywords, 
    datetime(changetime/1000000, 'unixepoch') AS last_updated, 
    milestone AS __group__, 
    reporter, owner 
    FROM ticket t 
    WHERE status NOT IN ('closed', 'resolved') AND milestone in ('$MILESTONE') 
    ORDER by t.milestone ASC, p.value 

但是，如果用戶沒有指定爲$MILESTONE的值，我想顯示結果爲每一個我們的三個團隊，通過團隊組合：

SELECT status, 
    id AS ticket, summary, priority, keywords, 
    datetime(changetime/1000000, 'unixepoch') AS last_updated, 
    milestone AS __group__, 
    reporter, owner 
    FROM ticket t 
    WHERE status NOT IN ('closed', 'resolved') AND milestone in ('project1', 'project2', 'project3') 
    ORDER by t.milestone ASC, p.value 

我怎麼能檢測一個變量是否在SQL查詢中設置或不？除此之外，當用戶第一次點擊報告時，有沒有簡單的方法可以設置$TEAM的默認值？

（注：如果有沒有的方式，跨越SQL實現的一般情況下，請取消收藏，這是「SQL」或張貼到該結果的評論，所以我可以做到這一點。）

Answer 1

您應該能夠在WHERE子句中使用CASE WHEN ELSE語句，如下所示：

SELECT status, 
id AS ticket, summary, priority, keywords, 
datetime(changetime/1000000, 'unixepoch') AS last_updated, 
milestone AS __group__, 
reporter, owner 
FROM ticket t 
WHERE status NOT IN ('closed', 'resolved') 
AND (CASE WHEN '$MILESTONE' != '' THEN (milestone='$MILESTONE') 
    ELSE (milestone in ('project1', 'project2', 'project3')) END) 
ORDER by t.milestone ASC, p.value