绝对高分请教：关于记录集__QueryString_createStatementResultSet_TYPE_SCROLL_SENSITIVE_CONCUR_READ_ONLY_smt_

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绝对高分请教：关于记录集

来源: 互联网发布时间：2015-08-11

本文导语: QueryString="SELECT * FROM GoodsInfo WHERE 商品条码='"+GoodsID+"'"; smt = con.createStatementResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY); rs=smt.executeQuery(QueryString); 如果没有找到符合条件的纪录，怎样得知？ | ...

QueryString="SELECT * FROM GoodsInfo WHERE 商品条码='"+GoodsID+"'";
smt = con.createStatementResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
rs=smt.executeQuery(QueryString);

如果没有找到符合条件的纪录，怎样得知？

if smt.nextnull then
...
else

设置异常处理啊
没有找到合适的记录，SQL自然规律回抛出一个异常，你扑获异常就可以了

此时rs.next()==false

try
{
QueryString="SELECT * FROM GoodsInfo WHERE 商品条码='"+GoodsID+"'";
smt = con.createStatementResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
rs=smt.executeQuery(QueryString);
while( rs.next() )
{
}
}
catch (Exception e)
        {
            System.out.println( "select: fail" + QueryString );
        }

boolean noRecordFlag = true;//无记录标志
try
{
QueryString="SELECT * FROM GoodsInfo WHERE 商品条码='"+GoodsID+"'";
smt = con.createStatementResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
rs=smt.executeQuery(QueryString);
while( rs.next() )
{
noRecordFlag = false;
}
}
catch (Exception e)
{
System.out.println( "select: fail" + QueryString );
}
if (noRecordFlag)
{
}
else
{
}
如果不怕麻烦就这样做。