I caused a BDC error this week that manifested itself on the user interface and in the 12 hive log at runtime.

First, this appeared in the user interface:

Could not find fields to insert all the Identifier Values to correctly execute a SpecificFinder MethodInstance with Name … Ensure input Parameters have TypeDescriptors associated with every Identifier defined for this Entity.

Here’s a screen shot:

I could also cause this message to appear in the 12 hive log at will (using my patented high-tech-don’t-try-this-at-home  "mysterious errors" method):

11/14/2007 09:24:41.27         w3wp.exe (0x080C)         0x0B8C        SharePoint Portal Server         Business Data         6q4x        High         Exception in BusinessDataWebPart.OnPreRender: System.InvalidOperationException: The Identifier value ”, of Type ”, is invalid. Expected Identifier value of Type ‘System.String’. at Microsoft.Office.Server.ApplicationRegistry.MetadataModel.Entity.FindSpecific(Object[] subIdentifierValues, LobSystemInstance lobSystemInstance) at Microsoft.SharePoint.Portal.WebControls.BdcClientUtil.FindEntity(Entity entity, Object[] userValues, LobSystemInstance lobSystemInstance) at Microsoft.SharePoint.Portal.WebControls.BusinessDataItemBuilder.GetEntityInstance(View desiredView) at Microsoft.SharePoint.Portal.WebControls.BusinessDataDetailsWebPart.GetEntityInstance() at Microsoft.SharePoint.Portal.WebControls.BusinessDataDetailsWebPart.SetDataSourceProperties()

I searched around and found some leads in the MSDN forum, but they weren’t enough for me to understand what I was doing wrong.  I watched a webcast by Ted Pattison that my company has squirreled away on a server and came to realize my problem.

In my ADF, I’m connecting to a SQL database as shown:

            <Property Name="RdbCommandText" Type="System.String">
              <![CDATA[
                SELECT
                      SETID, CARRIER_ID, EFFDT, DESCR, EFF_STATUS, TAXPAYER_ID, NETWORK_ID, FRT_FORWARD_FLG, ALT_NAME1, ALT_NAME2, LANGUAGE_CD,
                      COUNTRY, ADDRESS1, ADDRESS2, ADDRESS3, ADDRESS4, CITY, NUM1, NUM2, HOUSE_TYPE, ADDR_FIELD1, ADDR_FIELD2, ADDR_FIELD3,
                      COUNTY, STATE, POSTAL, GEO_CODE, IN_CITY_LIMIT, COUNTRY_CODE, PHONE, EXTENSION, FAX, LAST_EXP_CHK_DTTM, FREIGHT_VENDOR,
                      INTERLINK_DLL, TMS_EXCLUDE_FLG
                FROM
                      dbo.PS_CARRIER_ID_VW WITH (nolock)
                WHERE
                  (SETID <> 'SHARE') and
                  (lower(CARRIER_ID) >= lower(@MinId)) and
                  (lower(CARRIER_ID) <= lower(@MaxId)) and
                  (lower(DESCR) LIKE lower(@InputDescr))
                ]]>
            </Property>

I was provided that SQL from a DBA person and I’m given to understand that it’s a special view they created just for me.  The unique key there is CARRIER_ID.

Here is the bug I introduced:

      <Identifiers>
        <Identifier Name="CARRIER_ID" TypeName="System.String" />
        <Identifier Name="DESCR" TypeName="System.String" /> 
      </Identifiers>

Somewhere along the line, I had managed to confuse myself over the meaning of <Identifiers> and added DESCR even though it’s not actually an identifier.  I took DESCR out of the identifiers set and presto! It all worked.

I hope this saves someone some grief 🙂