The riddle of the working broken query

Question

I was going through some old code that was written in years past by another developer at my organization. Whilst trying to improve this code, I discovered that the query it uses had a very bad problem.

  OdbcDataAdapter financialAidDocsQuery =
            new OdbcDataAdapter(
                @"SELECT   a.RRRAREQ_TREQ_CODE, 
                           b.RTVTREQ_SHORT_DESC, 
                           a.RRRAREQ_TRST_DESC, 
                           RRRAREQ_STAT_DATE,
                           RRRAREQ_EST_DATE,
                           a.RRRAREQ_SAT_IND, 
                           a.RRRAREQ_SBGI_CODE, 
                           b.RTVTREQ_PERK_MPN_FLAG, 
                           b.RTVTREQ_PCKG_IND, 
                           a.RRRAREQ_MEMO_IND,
                           a.RRRAREQ_TRK_LTR_IND, 
                           a.RRRAREQ_DISB_IND, 
                           a.RRRAREQ_FUND_CODE, 
                           a.RRRAREQ_SYS_IND
                  FROM     FAISMGR.RRRAREQ a, FAISMGR.RTVTREQ b
                  WHERE    a.RRRAREQ_TREQ_CODE = b.RTVTREQ_CODE
                           and a.RRRAREQ_PIDM = :PIDM
                           AND a.RRRAREQ_AIDY_CODE = :AidYear ",
                this.bannerOracle);
        financialAidDocsQuery.SelectCommand.Parameters.Add(":PIDM", OdbcType.Int, 32).Value = this.pidm;
        financialAidDocsQuery.SelectCommand.Parameters.Add(":AidYear", OdbcType.Int, 32).Value = this.aidYear;
        DataTable financialAidDocsResults = new DataTable();
        financialAidDocsQuery.Fill(financialAidDocsResults);
        FADocsGridView.DataSource = financialAidDocsResults;
        FADocsGridView.DataBind();

The problem is that the column a.RRRAREQ_TRST_DESC does not exist. A fact you learn very quickly when running it in Oracle SQL Developer.

The strange thing?

This code works.

The gridview binds successfully. (It doesn't try to bind to that field.) And it's been in production for years.

So, my question is...why? I've never seen a bad query work. I've never seen Oracle allow it or a data provider hack around it.

Does anyone have any idea what's going on here?

Answer 1

Hmmm...A few things to check:

1. Does this code actually run? It may seem silly to suggest this, but there may be a newer file that replaced this one.

2. Is an exception being squelched by your code? (Anyone who would name columns like that is definitely capable of squelching those pesky exceptions)

3. Is the exception being squelched by 3rd party code? (Not as likely, but sometimes 3rd party code prefers to use annoying error codes instead of exceptions).

Past those suggestions, I'm not sure.

EDIT:

Revisiting the 2nd point, if you are working in ASP.NET, check that there is no global-level exception handler that is squelching exceptions. I ran into that problem on one site that I worked on and found dozens of exceptions in a single day.