Ibatis SQL Query检查表中是否存在Column

Question

什么是Ibatis SQL查询来检查表中是否存在列。我尝试了以下但是它给出了一个错误：

<select id="getAllAccountsWithLastName" resultClass="com.replication.Account">
   if  exists(select * from Information_schema.columns WHERE table_name='UserName' AND column_name = 'LastName')
           begin
           EXEC('select Acc.Acc accountNumber,
                              Acc.AccName description,
                              Acc.Staff staff,
                              UserName.LastName lastName,
                              RiskProfile.ProfileDesc riskProfileDesc
                         from Acc
                         join UserName on (Acc.AccID = UserName.AccID)
                    left join RiskProfile on (Acc.RiskProfileID = RiskProfile.RiskProfileID)
                        where Acc.AccStat = ''A''')
           end
</select>

ERROR

    Invalid column name 'LastName'.

相同的查询在SQL Server中有效。