我试图在数据库表和数据库表中增加一栏。
PreparedStatement ps = con.prepareStatement(query);
ps.execute();
ps.close();
问 问 问 题(validkou)
ALTER TABLE mytable ADD COLUMN mycolumn datatypeinfo
无论如何,它执行罚款,并设立一栏。 但执行声明有误。 我以处决方式进行了审判,返回人数为零。
Note that this whole thing is within a transaction with con.setAutoCommit set to false. So I am not sure if that is the problem. The issue is that I have to create the column before I can go ahead with other update queries. So it has to run in a transaction.
The return value of execute() does not indicate whether it was successful, but if the query that was run returned a result.
由于execute(> 正确返回false
Quote from the Javadocs :
Returns:trueif the first result is a Result 物体:false 如果第一个结果是最新数字,或没有结果。
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