sp_executesql"存储过程需要单个字符串参数@statement 来执行.

The "sp_executesql" stored proc expects a single string parameter @statement to execute.

您的字符串在这里完全不正常.....您需要在任何固定"字符串部分前面加上 N'......' 以使其成为 Unicode 字符串，但这绝对不是正确的案例在这里.

Your string is totally out of whack here..... you need to prefix any "fixed" string parts with a N'......' to make them Unicode strings, but this is definitely not properly the case here.

我想你可能想试试这个:

I think you might want to try this:

DECLARE @a INT 
DECLARE @b VARCHAR(2)

SET @a = 1

DECLARE @statement NVARCHAR(500)

WHILE @a < 30
BEGIN
    SET @b = CAST(@a AS VARCHAR(2))

    SET @statement = 
        N'update source_temp set pmt_90_day = pmt_90_day + ' + 
             'convert(money, ''trans_total_' + @b + ''') ' + 
             'where convert(datetime, ''effective_date_' + @b + ''')' +
             ' <= DATEADD(DAY, 90, ORSA_CHARGE_OFF_DATE) ' +
             'and DRC_FLAG_' + @b + ' = ''C'''

    exec sp_executesql @statement

    SET @a = @a + 1
END

这是否有效并达到您的预期?

Does this work and do what you expect it to do??

说明:N'.........' 分隔包含 SQL 语句的整个字符串.必须复制(转义")内的任何撇号.我希望我能正确理解你的逻辑.

Explanation: the N'.........' delimits the whole string which contains the SQL statement. Any apostrophe inside that has to be duplicated ("escaped"). I hope I understood your logic correctly.

马克