- SUBSTRING 函數(shù)用于截取指定長度的字符串，并將截取的字符串返回
SUBTRING(expression,start,length);
SELECT SUBSTRING('aabbcc',3,2);
SELECT SUBSTRING('aabbcc',3,LEN('aabbcc'));
SELECT SUBSTRING('aabbcc',3,100); -- 截取超過字符串長度不會報錯宵统，返回從截取起始位置到最后的字符串
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SELECT * FROM Subject WHERE ID=4;
SELECT SUBSTRING(Description,3,6) AS New_Description FROM Subject WHERE ID=4;
SELECT SUBSTRING(Description,3,100) AS New_Description FROM Subject WHERE ID=4;
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- SUBSRTING 與 STUFF 對比
同樣都是對字符串進(jìn)行截取操作，SUBSTRING 是返回的結(jié)果是被截掉的部分劳吠，STUFF 返回的結(jié)果是截取后剩余的其他部分
