插入现有记录时子查询有什么问题

您需要删除VALUES关键字

INSERT INTO RDT_ATTACHMENTS
SELECT (SELECT MAX(id) FROM RDT_ATTACHMENTS), 
        1363,
        fname,
        fpath,
        fsize,
        description,
        refentity,
        uploadby,
        uploadon,
        originalfname,
        LATEST   
FROM RDT_ATTACHMENTS 
WHERE id = 68

请尝试此查询:

insert into RDT_ATTACHMENTS
select  
    MAX(id) over(), -- (SELECT MAX(id) FROM RDT_ATTACHMENTS) to get the max(id) of table
    1363, 
    fname,
    fpath,
    fsize,
    description,
    refentity,
    uploadby,
    uploadon,
    originalfname,
    LATEST   
from RDT_ATTACHMENTS
where id = 68

提供的表格 RDT_ATTACHMENTS 在select中按相同顺序具有相同数量的列。