I'm loading a subset of the parent records and the child records into a dataset then setting datarelations and foreignkeyconstraints, so when I am building the dataadapter select stmt for the child records, I must make sure that only the child records whose parent is present is loaded to avoid referential integrity errors. Since the subset of the ParentTable has been loaded into a dataset I tried:
daChild = new OleDBDataAdapter(CreateOledbCommand("select * from Childtable where ChildKey in (ds.tables(""ParentTable""))",dconn))
But got an "undefined function 'ds.tables' in expression" error at runtime.
So, I tried to create a one column table to pass to the IN clause, like this:
Dim MyDataView as DataView = New DataView(ds.tables("ParentTable"))
Dim MyTempParentTable as DataTable = MyDataView.ToTable(False, "ParentKey")
daChild = New OleDbDataAdapter(CreateOledbCommand("select * from ChildTable where ChildKey in (MyTempParentTable)", dconn))
I checked in the debugger, and MyTempParentTable is, in fact, a one column table containing the key of the ParentTable. I thought that the IN clause could take a one column datatable as valid input. Apparently not, as I am getting a "No value given for one or more required parameters" error at runtime.
I'm just about out of ideas. All my google searching came up with for the IN clause was something like IN (value1, value2, value3...) and doesn't give any examples for the IN clause containing a more complex expression.
Can anyone clue me in on what I'm missing, or maybe a different way to accomplish this? I'm trying to get the IN clause to work because I'm thinking that it is the most efficient way to do this... Maybe it's not... Thanks for any help.
I haven't found an answer to the question about why the IN clause didn't work, but just in case anybody else has this issue I will post my workaround.
I load the parent records as usual, but my dataadapter select stmt for the child records has a "WHERE 1=0" so that zero records are initially loaded. When a new parent record is displayed I then determine if the child records for that parent are already loaded into the dataset, if not, I load them in. Bottom line is that I don't pre-load the child records, rather, I load them "on demand". This solution is working well for me.
Related
I have a PostgreSQL table in an application that holds both parent and child records. There is a column in the table to reference the the parent id where applicable for each child record. The problem is I am trying to import data from an external source where the child record is made up of a sub number of the parent. eg parent_reference_id = 123456000000 and a child_reference record for this could 123456000001, 123456000002 and so on. The application itself generates a unique id for each record when I import the data and so its possible to import the child and parent records simultaneously, however the difficulty I'm facing is linking the application generated id for the parent record to the parent_reference_id for the corresponding child records. The only hook I have is that the 1st six digits of the child_value_reference match the 1st six digits of the parent_value_reference and I've tried something like foo = bar(left(value,6)||'000000'; to create a match. However, I don't know how to use this to return the unique_id in a meaningful way and update the matching records. I've tried temporary tables and cte, however my knowledge of postgres is limited and I can't seem to find a solution that fits my problem. Another thing to mention is that these groups can change with updates within the external data so i'd also need a solution to make those updates too. Thanks in advance, Crispian
I have a Crystal Report with a database command:
The command has a join clause that can be removed and read from a table in the database, because it represents static data. I add this table (called _System) to the database expert:
Now I edit the command to remove the join and columns that reference this table. Since the report fields that depended on these columns are no longer mapped, this causes the Map Fields window to appear:
...which does not have the new table in it. If I cancel out of this I am back to where I originally was. If I hit OK without mapping, all of the unmapped fields on the report are deleted (suffice it to say... I was not expecting this >:( )
I have tried adding links between the command and the new table, and refreshing report parameters, but these have had no effect.
One workaround is to manually replace every field in the report, but this is very labour intensive.
Here is the outline of the command before:
SELECT ACT.Account_Code, ACT.Company, ACT.FName, --etc
STM.CompanyName AS 'DLRName', STM.Address_1 AS 'DLRAddress', STM.City AS 'DlrCity' --etc
FROM Accounts AS ACT
JOIN _System AS STM ON 1 = 1
GROUP BY ACT.Account_Code, ACT.Company, ACT.FName, --etc
STM.CompanyName, STM.Address_1, STM.City --etc
And after:
SELECT ACT.Account_Code, ACT.Company, ACT.FName, --etc
FROM Accounts AS ACT
GROUP BY ACT.Account_Code, ACT.Company, ACT.FName --etc
I have removed the JOIN on the _System table, and all referenced columns.
It appears to not be recognizing your _system table as a new source.
I would :
1) leave your command object SQL unchanged & get the issue worked out with the _System table, then
2) ensure that you are able to establish a join between the command object fields and the _System table fields, and lastly
3) then remap the fields.
Step two I suspect is the source of the problem, as your join condition is "ON 1 = 1" which I assume to mean that you may not have a common key field in both tables.
Note that your original command SQL selects STM.Companyname AS 'DLRName'.
Hence, crystal now know of a field called DLRName, but does not know of a field called CompanyName, hence it cannot make the association between DLRName in the old source, and CompanyName in the new source...
Likewise with the rest of the fields that are being moved from the command object to an attached table. if no name match exists...Crystal cant make the connection. However...it would list all unmatched fields that are on the report, and all unused fields in the recognized data sources, and allow you to specify the matches yourself.
But it does not...which tells me that something has gone wrong with the attempt to attach/open the _System table. Hence..you need to get that worked out first, then make the field adjustments.
If this doesnt get you thru...then show some sample data so I can see how the two tables are relating ( ensure some examples exists where there is a row match from both tables ).
I had the same problem a while ago.
Unfortunately I can't find anything online that helps, or maybe wasn't looking hard enough. I just noticed that in my case, that particular field that isn't showing in the map field dialogue box has nvarchar(max) as its datatype (in view).
I tried to force the datatype with CAST(missingfieldname as nvarchar(20)) as missingfieldname (I did this in the view), and voila, it magically appears in the map field dialogue box.
It seems that field mapping dialogue box aren't showing fields with blob texts.
I know this question was asked 4 years ago. But hopefully, this comment could help future solution seekers regarding this absurd and weird problem. I just got lucky seeing what's unique about that particular missing field.
Basically, I want to insert rows in the form InventJournalTransfer. I added a menuitem button that calls a class which opens a dialog where I fill a WMSLocationId, then I loop on Inventsum table to get all ItemIds with Available qty for this WMSLocationId and insert them into InventJournalTrans Table.
The code I wrote seems to be working as I have correct records inserted in my table(visible in Table browser, correct journalId, linenum itemId, qty etc...) BUT the records inserted do not appear in my form. I tried to refresh my form with or without code, but my grid's still empty.
I had a look at the class InventCountCreate that does what I want to do in a different journal type, but as I'm quite a newbie it is difficult for me to understand exactly how this class works.
Could anyone explain to me how to display my inserted rows in my form or give other leads?
The InventJournalTrans is table is inner joined to two InventDim, one related via the InventDimId field, the other via ToInventDimId.
Both fields must be filled with a valid InventDimId to an existing InventDim record for the form to show the record.
Have you tried right-clicking on your form's node in the AOT and clicking "Restore"? Perhaps your form is still using cached data.
So I basicly have a table which has a list of table names. All these listed tables have exact same structure.
Then I have a query template, with place holder for table name.
I need to create a view, which should return results of that query UNIONed from all the tables listed in that one setup table.
So far what I've done is create a user defined function, which would prepare a complete UNIONed SQL statement.
But this is where I'm stuck. I can't figure out how to execute it in a view and return whatever it returns..
My function returns SQL syntax.
I figured that UDF can't executed dynamic sql, so my method won't work. So far I've solved my issue at hand by generating views. But I would still prefer a more dynamic way..
Can any one help me why this error occurs when i update using sqlDataadapter with join query
Dynamic SQL generation is not supported against multiple base tables.
You have a "join" in your main query for your dataset (The first one in the TableAdapter with a check by it). You can't automatically generate insert/update/delete logic for a TableAdapter when the main query has multiple tables referenced in the query via a join. The designer isn't smart enough to figure out which table you want to send updates to in that case, that is why you get the error message.
Solution. Ensure that your main query only references the table you want the designer to write insert/update/delete code for. Your secondary queries may reference as many tables as you want.
It was in the case that i was trying to set value for identity column in my datarow. Simply i deleted the code to set value for identity column and it will work.
My Scenario:
Database:
uin [primary, identity]
name
address
Whenever i tried to set the datarow("uin") the error occurs. But works fine with datarow("name") and datarow("address").
Hope it works for you too