I am using Delphi 2010 and UIB to access a Firebird database.
I am trying to run the Query
SELECT
RECID
FROM TABLE
WHERE ((:DX = '') OR (DX=:DX))
AND ((:POSTCODE='') OR (POSTCODE=:POSTCODE))
Note, that I am using each named parameter twice in the statement.
When I prepare it in a TUIBQuery I get ParamCount=2 and two parameters named DX. When I trace the code I see TSQLParams.Parse passing over the my SQL and calling AddFieldA four times. I can see that duplicates are recognized and added to the end of FXSQLDA, but FParamCount is not incremented.
As a temporary dumb fix I have added such an increment and I now get (DX, DX, POSTCODE, POSTCODE) as parameter-list. That sort of works.
Questions:
Is the sort of parameter-reuse I am attempting supported by Firebird?
By UIB?
Is my fix viable?
Are there better fixes?
Firebird itself does not support named parameters in dynamic SQL (it does in procedural SQL). Firebird only supports positional parameters.
So it is your driver that translates named parameters to positional.
Related
Windows 10, Access 2016
I am moving a very small database (14 tables and 40-50 stored procedures) from SQL Server to Access. I have tried to recreate the stored procedures from code using an OLEDB command object. This is a sample of a CommandText…
CREATE PROCEDURE DeleteOrderDetailByOrderID
([#ID] int)
AS
DELETE FROM OrderDetails
WHERE (OrderID = #ID);
I get an error message that the Data Type of #ID is incorrect. It is not. When I remove the brackets from #ID all is forgiven and the code runs. However, Access strips the # from #ID in the parameter section (not in the Where clause). I have had to go into Access and manually correct this. I do not like the idea of going through almost 5000 lines of code to correct parameter names in my program. I thought I could use the direct approach by pasting the SQL directly into Access but I get an error with this route saying syntax error in CREATE TABLE and it highlights the word PROCEDURE. This leads me to believe that you cannot use CREATE PROCEDURE directly in Access. Is this true? Is there another approach that I am missing?
You are missing, that T-SQL of SQL Server is not Access SQL.
Access has UDFs - user defined functions - that can be used in queries also, but that is VBA code.
If you just need a single-user file based database to hold your data, you may get away with the SQL Server Compact Edition which supports a subset of T-SQL.
I'm updating an ancient codebase written in Delphi 7 using ODBC Express for database connectivity to Delphi Seattle 10 using FireDAC. Currently, ODBC Express OEDataset components are pointed at stored procs and defined with params at design-time, including an #Result param populated from the "Return" function of the Sybase SPs.
If I attempt a simple swap (with minimal adjustment) for FireDAC's TFDStoredProc component (defining params at design-time), I get an "invalid parameter type" error when I include the #Result parameter (DataType=ftInteger, ParamType=ptResult). Without the #Result parameter, the stored procedure executes fine, but then I can't access the "Return" value.
I've mucked about with ResourceOptions.UnifyParams, FetchItems.Items := [fiMeta], ExecFunc instead of ExecProc, leaving out the #Result param, etc etc.
I'm sure I'm missing something very obvious, but I've been banging my head on my desk for a day trying to figure this out. Does anybody have any advice?
As weird as it seems, the issue is simply that the ptResult parameter was added as the last parameter in the list (which is how it was done using ODBC Express). Moving the #Result param to the first position, and only the first position, fixes the issue. Now I'm going to have to scour the documentation to see where I missed that little tidbit...
I was using UniDac for a long time now and decided to move on to FireDac as it has good Asynch methods after moving on i saw that none of my data editing works anymore it gives me an error:
[FireDAC][Phys]-330. Cannot generate update query. Update table undefined.
What I am trying to do here is i have a TFDStoredProc component who gets all the data from the database and lets me edit it, with unidac I could easily edit the data without any problem like this:
StoredProc.Edit;
StoredProcCreatedID.Value := SomeValue;
StoredProc.Post;
and it worked, but with AnyDac it doesn't, I tried specifying manually the UpdateTable which leads to another problem:
[FireDAC][Phys][ODBC][Microsoft][SQL Server Native Client 11.0][SQL Server]Invalid column name 'CreatedID'.
I am using Microsoft SQL Server 2012 FireDac 8.0 and stored procedures for getting back results any ideas?
P.S.
The query looks like this
SELECT
CreatedBy as CreatedID,
usr.UserName as CreatedBy
FROM
Sales
LEFT JOIN
Users usr ON usr.ID = Sales.CreatedBy
it looks like the FireDac update builder doesn't recognize the aliases on the fields, any help would be appreciated.
Well i figured out what was the issue, it seems that if you specify a alias in the query for a field the Origin property will be set to the alias and not the real field i downloaded CNPack a must have for a delphi developer also its free, ran the component selector and changed all my aliased fields to their real fields and it works, but this is still a big issue in FireDac component because it doesnt recognize the aliased fields, lets hope it will be fixed in the future as to specify for every query what table it should update and what fields that just allot of work if you are migrating from a big project in my case 220+ stored procedures.
I am trying to use Macros in FireDAC to Preprocess my SQL Queries. I have a TADQuery object on a Data Module with the SQL set to something like:
Select * from MyTable
join OtherTable on MyTable.Key = OtherTable.Key
&Where
Then in my code I do this:
WhereClause = 'stuff based on my form';
Query.MacroByName('Where').AsRaw := WhereClause;
Query.Open;
This has worked great for complicated queries because it lets me make sure my fields and join conditions are correct using the SQL Property editor.
My problem is when the SQL statements ends up invalid because of my where clause. Is there any way to see the SQL after pre-processing that is going to be executed? Right now I am catching the FireDac errors and showing the SQL that is on EADDBEngineException object. However that is still showing my original SQL with the macros. If I can't get to it after the error happens is there anyway to force the Macro replacement to take place so I can look at the SQL in the debugger to help me see what is wrong.
If it matters I am connecting to a MS Access database with the goal of moving to SQL Server in the near future.
Apart from using Text property, to monitor what SQL is actually going to the database engine, consider using the "FDMonitor" FireDAC utility. According to the DokWiki pages (below):
drop a TFDMoniRemoteClientLink component on your form,
Set its Tracing property to True,
Add the MonitorBy=Xxx connection definition parameter to your existing FDConnection component. You can do this in the IDE object inspector, by selecting your FDConnection component, expanding the Params property, and setting MonitorBy to mbRemote.
Note that the TFDMoniXxxxClientLink should come before TFDConnection in the data module or form creation order, so adjust this by right clicking on the form or data module, then Creation Order, and moving the TFDMoni.. component above the FDConnection.
Also, it's helpful in the options of the TFDMoniXxxxClientLink, to disable most of the events being recorded, otherwise all the data returned is also shown in the FireDAC monitor. Expand the EventKinds property, and turn all the event kinds off, except for perhaps ekConnConnect, ekConnPrepare, and ekCmdExecute.
Then open the FireDAC Monitor from the IDE, (Tools > FireDAC Monitor). Start your app only once the monitor is running. Double click on a trace event (in the Trace Output tab), and you will see the actual SQL sent to the database in the bottom pane.
It also seems likely that adding the EventType of ekConnPrepare as mentioned above, would show you when the query's Prepare is called, but I haven't played enough with it say for sure.
Please see the following pages on the DocWiki for more information:
Overview: FDMonitor
How to: Tracing and Monitoring (FireDAC)
Other FireDAC utilities: Utilities (FireDAC)
(Just to remove this question from list of unanswered questions)
From comments:
Well, I've roughly checked what's happening there and I'm still not
sure if calling Prepare (which is useless for you as I get) is the
minimal requirement to trigger that preprocessing. Though, the
preprocessed SQL, the one which is sent to the DBMS you can access
through the Text property (quite uncommon name for such property). – TLama Feb
21 '14 at 8:18
I have a very large block of SQL that I am trying to execute inside of Delphi, against a Microsoft SQL Database. I am getting this:
Multiple-step OLE DB operation generated errors.
Check each OLE DB status value, if available. No work was done.
The script has multiple sql IF statements followed by BEGIN and END blocks with invocations of stored procedures, declaration of variables, and EXEC inside that. Finally it returns some of the variable values by SELECT #Variable1 AsName1,#Variable2 AsName2....
The above multi-step error is coming in as an OLEException from ADO, not from the Delphi code, and happens after all the SQL exec-stored-procedure have occurred, and therefore I suspect it's firing this OLE exception when it reaches the final stage which SELECT #Variable1 AsName1,... to get back a few variable values for my program to see them.
I know about this retired/deprecated MS KB article, and this is unfortunately not my actual issue:
http://support.microsoft.com/kb/269495
In short that KB article says to fix a registry key and remove "Persist Security Info" from the connection string. That's not my problem. I'm asking this question because I found the answer already and I think that someone else who gets stuck here might not want to waste several hours finding potential issues when there are several that I have found after searching for solutions for several hours. Anyone who wants to add another answer with different options, is fine, and I'll select yours if it's reproducible, and if necessary I'll turn this one into a Community Wiki because there could be a dozen obscure causes for this "ADO recordset is in a bad mood and is unhappy with your T-SQL" exception.
I have found several potential causes that are listed in various sources of documentation. The original KB article in the question suggests removing the 'Persist Security Info' from my ADO connection string, however in a standalone test in an application with just a TADOConnection and a single TADOQuery, the presence or absence of Persist Security Info had no effect, nor did explicitly setting it True or False.
What DID fix it was removing this CursorType declaration:
CursorType=ctKeyset
What I have learned is that bidirectional ADO datasets are fine for SELECT * FROM TABLE in ADO but are not so fine for complex SQL scripts.
Potential source of this error is updating char field with large value.
Example: Form has edit box with max length property set to 20 characters and Oracle database table has field defined as char(10).
Updating with 10 characters (or less) will work fine while updating with more then 10 characters will cause 'Multiple step...' error on ADOQuerry.UpdateBatch().
You also have to know that CHAR will allways have 20 characters. Consider Trimming value in edit box. CHAR behaves different than VARCHAR2 type.
If you have a query with parameter ,check the number of parameters in the query is matched with script...!