此方法可以解决查询某字段中数字部分为固定值的记录，字母部分为定值类似
代码如下:create function dbo.F_Get_No
(
@No varchar(100)
)
RETURNS bigint
AS
BEGIN
WHILE PATINDEX('%[^0-9]%',@No)>0
BEGIN
SET @No=STUFF(@No,PATINDEX('%[^0-9]%',@No),1,'') --删掉一个非数字的字符，循环结束，剩余的为数字部分
END
RETURN CONVERT(bigint,@No)
END
此函数可以返回某字符串中的数字部分
PATINDEX函数 返回所查内容在字符串中第一次出现的索引
STUFF函数 删除指定长度的字符并在指定的起始点插入另一组字符。
select F_Get_No('sdsdf2334sfsd234') 返回'2334234'
注明：此方法可以解决查询某字段中数字部分为固定值的记录，字母部分为定值类似
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