相关疑难解决方法(0)

我有以下代码:

        var query = Database.SqlQuery<int>(@"

            SELECT CASE WHEN EXISTS (
                SELECT 1 
                FROM v$session v, UsersXxxx u
                WHERE v.Client_Info LIKE u.UserName || ';%' 
                AND v.UserName = :schemaName
                AND u.SchemaName = :schemaName
                AND v.module = 'XXXX.exe' 
                AND u.UserKey = :userKey)
            THEN 1 ELSE 0 END AS LoggedIn FROM DUAL",

            new OracleParameter("schemaName", schemaName),
            new OracleParameter("userKey", userKey));

        return query.First() != 0;

这产生了"ORA-01008:并非所有变量都受到约束".我怀疑变量被绑定的方式出现了问题并最终尝试了这个:

        var query = Database.SqlQuery<int>(@"

            SELECT CASE WHEN EXISTS (
                SELECT 1 
                FROM v$session v, UsersXxxx u
                WHERE v.Client_Info LIKE u.UserName || …