SQL Server 查詢本周每日數據：CONVERT 按日期分組彙總

需求：任意時間範圍內，按天分組統計消費金額與地點（多地點怎麼辦？取首末或拼接）。

核心查詢

SELECT 
    CONVERT(date, cardday) AS day,
    SUM(amount) AS total_amount,
    STRING_AGG(place, ',') AS places -- SQL Server 2017+
FROM tbl_consumption
WHERE cardday BETWEEN @start AND @end
GROUP BY CONVERT(date, cardday)
ORDER BY day;

舊版本無 STRING_AGG 可用 STUFF + FOR XML PATH 拼接地點。CONVERT(date, ...) 去除時間部分實現按天分組。