Additional rows appended to a DataTable are returned when the RowStateFilter is DataViewRowState.ModifiedCurrent, even if they have not been edited by the user.
And the DataTable RowChanged event fires when the DataTable is first populated by a select from the database, before any edits have taken place.
Is there any convenient way to tell if a row is actually dirty?
You can keep a copy of the original record to compare against and make the is dirty determination at the point you need to know whether it's dirty.
Check the datarow's rowstate property and if Modified compare the values in the Current and Original DataRowVersions.
See the following stack answer which includes code that may give you some pointers on how to implement this.
Related
I have a form linked to a table. I am trying to use the me.dirty function to see if the user changed anything. For now I put the code msgbox(me.dirty) in the form close button to determine what is happening. When some fields are changed i get true others i get false. For now I am only changing one field at a time. I have determined that if I look at the table before I close the form, if the table matches the form me.dirty is false. if not then me.dirty is true. this makes sense I dirty=true when the form does not match the table.
What I cannot figure out is why some field match the table and others do not until the form is closed. For example I have two check boxes one is always matching the table as soon as i check or uncheck it and dirty = false. The other one does not change the table until I close the form and dirty=true. Iv'e looked at all the properties of the two check boxes and they are the same.
I also have two drop downs that give me dirty=true and two text boxes that always give me dirty = false. (both cases when the field is changed.)
Any help would be appreciated as I am stumped right now.
OK I figured it out on my own. The ones where me.dirty=false had an event after update that put focus on a subform, this updated the table and then when clicked the button to run me.dirty, it was false.
When I try to update a database with some modified values in a dataset, a concurrence exception doesn't raise if i change manually some values in the database after the fill method on the dataset is performed. (I only get the exception if I delete a row manually and then I try call the method update of data adapter).
How should I check if I have a "dirty read" on my dataset?.
You have several options.
Keeping a copy of the original entity set to compare against and make
the is dirty determination at the point you need to know whether it's
dirty.
Checking the datarow's rowstate property and if Modified compare
the values in the Current and Original DataRowVersions. If the second
change makes the value the same as the original then you could call
RejectChanges, however that would reject all changes on the row. You
will have to manually track each field since the dataset only keeps
per-row or per-table changes.
I have a table called transactions. Within that is a field called ipn_type. I would like to create separate table occurrences for the different ipn types I may have.
For example, one value for ipn_type is "dispute". In the past I would create a global field called "rel_dispute" and I would populate that with the value of "dispute". Then I could create a new table occurrence of the transactions table, and make a relationship based on transactions::ipn_type = transactions::rel_dispute. This way only the dispute records would show up in my new table occurrence.
Not long ago, somebody pointed out to me that this is no longer necessary, and there is a simpler way to setup such a relationship to create a new table occurrence. I can't for the life of me remember how that was done, though.
Any information on this would be greatly appreciated. Thanks!
To show a found set of only one type, you must either perform a find or use the Go to Related Record script step to show only related records. What you describe as your previous setup fits the latter.
The simpler way is to perform a find - either on demand, or by a script triggered OnLayoutEnter.
The new 'easy' way is probably:
using one base relationship only and
filtering only the displaying portal by type. This can be done with a global field, a global variable containing current display type. Multiple portals with different filter conditions are possible as well.
~jens
I have a form in Access where I have 2 unbound multi-select listboxes, with some code to move items between them.
Each of the fields in the table which are shown in the listboxes are boolean values - if the value is true then the name of that field shows up in lstSelected, and if false shows up in lstUnselected.
The listboxes have a RowSourceType of Value List, and the value list is generated programatically by looking at the underlying record and constructing a string with the field names where the boolean values are true for lstSelected and False for lstUnselected.
On the form I have two buttons, cmdMoveToSelected and cmdMoveToUnselected. When I click on cmdMoveToSelected it changes the boolean value of the underlying field for any selected items in the lstUnselected listbox from false to true by executing an SQL string, then rebuilds the value lists for both of the listboxes.
I have all of this working just fine. If I do a me.lstUnwanted.requery and a me.lstwanted.requery then everything moves and shows up correctly, and the underlying fields are edited correctly, BUT when I click on anything else on the form I get the error:
The data has been changed.
Another user edited this record and saved the changes before you attempted to save your changes.
Re-edit the record.
Now I've found a way around this (jobDetailsID is the primary key of the record being dealt with):
Dim intCurID as Integer
intCurID = Me.JobDetailsID
Me.Form.Requery
Me.Recordset.FindFirst "JobDetailsID = " & curID
This requeries the form and then moves back to the current record, and this gets rid of the error, however it causes there to be a delay and the form to flicker while it opens back at the first record, changes back to the correct record and repopulates the list boxes.
Is there a way to do away with this error, or get it to trigger programmatically so I can catch it by turning the warnings off via vba?
Thanks in advance.
Maybe it helps not to bind the form to the table being altered by cmdMoveToSelected, but to a query that doesn't contain all the boolean fields. If cmdMoveToSelected alters one or more boolean fields, the record is changed, but the query result isn't. Not sure if it's sound though.
It also sounds a bit like a design problem rather than a form problem, storing options in boolean fields instead of into a related table.
Probably the best solution would be to not directly update the current record in the table while the Form is dirty. Instead, update the values of the fields within the form itself (Me!FieldName) as the items are moved from one List Box to the other, and let the form write those values back to the table as usual.
I seem to have fixed it, though the fix doesn't make a great deal of sense to me.
I added in a Me.Refresh to the button click code, after I had requeried the two listboxes and it appears to have stopped the message from coming up. However this only works when I have the JobDetailsID textbox visible on the form (though I expect this is arbitrary and any field-linked textbox would work).
Can anybody explain to me why this works? I'd like to understand fully when to use requery, refresh etc
I've had this sort of thing happen when I've left the form RowSource query hanging in place after converting the controls to unbound textboxes, etc. The general Form rowsource query (to bring in all fields I might possibly end up using) provides me with a query-list identical to the table fieldnames, making it simple to select them for control-names as needed. Works fine, but you have to remove the form rowsource query after all the names are matched-up. (After which DLookup and BeforeUpdate works for getting and storing values and changes.)
I have a FileMaker script which calculates a value. I have 1 record from table A from which a relation points to n records of table B. What is the best way to set B::Field to this value for each of these n related records?
Doing Set Field [B::Field; $Value] will only set the value of the first of the n related records. What works however is the following:
Go to Related Record [Show only related records; From table: "B"; Using layout: "B_layout" (B)]
Loop
Set Field [B::Field; $Value]
Go To Record/Request/Page [Next; Exit after last]
End Loop
Go to Layout [original layout]
Is there a better way to accomplish this? I dislike the fact that in order to set some value (model) programmatically (controller), I have to create a layout (view) and switch to it, even though the user is not supposed to notice anything like a changing view.
FileMaker always was primarily an end-user tool, so all its scripts are more like macros that repeat user actions. It nowhere near as flexible as programmer-oriented environments. To go to another layout is, actually, a standard method to manipulate related values. You would have to do this anyway if you, say, want to duplicate a related record or print a report.
So:
Your script is quite good, except that you can use the Replace Field Contents script step. Also add Freeze Window script step in the beginning; it will prevent the screen from updating.
If you have a portal to the related table, you may loop over portal rows.
FileMaker plug-in API can execute SQL and there are some plug-ins that expose this functionality. So if you really want, this is also an option.
I myself would prefer the first variant.
Loop through a Portal of Related Records
Looping through a portal that has the related records and setting the field has a couple of advantages over either Replace or Go To Record, Set Field Loop.
You don't have to leave the layout. The portal can be hidden or place off screen if it isn't already on the layout.
You can do it transactionally. IE you can make sure that either all the records get edited or none of them do. This is important since in a multi-user networked solution, records may not always be editable. Neither replace or looping through the records without a portal is transaction safe.
Here is some info on FileMaker transactions.
You can loop through a portal using Go To Portal Row. Like so:
Go To Portal Row [First]
Loop
Set Field [B::Field; $Value]
Go To Portal Row [Next; Exit after last]
End Loop
It depends on what you're using the value for. If you need to hard wire a certain field, then it doesn't sound like you've got a very normalised data structure. The simplest way would be a calculation in TableB instead of a stored field, or if this is something that is stored, could it be a lookup field instead that is set on record creation?
What is the field in TableB being used for and how?