擅长:python、mysql、java
<p>可能是确切的要求还不清楚的问题。但是,如果您只是想解决错误并找到Id的最大值,那么更改<code>sql</code>查询应该会有所帮助</p>
<pre><code> removed Id, text columns from select this query will give absolute max value of ID
select max(Id) as lastid from Table1 where dataexecuted IS NULL AND text is not null
added Id, text in group by this query will give max Id for each set of text column value.
select max(Id) as lastid, Id, text from Table1 where dataexecuted IS NULL AND text is not null group by Id, text
</code></pre>
<p>使用哪个查询取决于您的需求</p>
<p>而且不需要使用<code>for</code>循环来迭代结果集,从数据库中查找<code>max</code>值或任何<code>aggregate</code>值,这不是一种非常有效的方法</p>