SQL 如何将空表的 MAX() 视为 0 而不是 NULL
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How to treat MAX() of an empty table as 0 instead of NULL
提问by Mariusz Jamro
I try to select max value from table
我尝试从表中选择最大值
SELECT MAX(cid) FROM itemconfiguration;
However when table itemconfigurationis empty the MAX(cid)statements is evaluated to NULLwhile i need a number. How to handle this and treat NULLas 0 ?
但是，当表itemconfiguration为空时，MAX(cid)语句被评估为，NULL而我需要一个数字。如何处理这个并将其NULL视为 0 ？
回答by RB.
回答by zibidyum
SELECT NVL(MAX(cid), 0) FROM itemconfiguration;
SELECT NVL(MAX(cid), 0) FROM itemconfiguration;
回答by mrm aadil
Can replace a number when max return null using ISNULL,
可以在 max 返回 null 时使用ISNULL替换数字，
ISNULL(MAX(cid),0) FROM itemconfiguration;
