In a Related Tables, you need to enter a FK to link to the parent table.
You either key in the FG from memory !!!!!! or use help.
The standard procedure is to design the field as combo box AND use SQL to select the field that will help to input the ID of the parent table. So, if you want to input foreign key 3 , the combo box will display what 3 is then when you selected Access will insert 3 for you.
My question is since I can later on, edit the table and change the the value to another value, and mess the whole thing up!!! HOW can I lock my first choice so it will stay unedited ?
My second question is: Is this the only way to input the FK if you do not remember the exact ID number or there are thousands of records in the parent table.?
Re. #1
In Access 2010 you could use a trigger to check whether the value has been used in another table as a FK and not allow the change. In previous versions all you could do, would be to hide the navigation pane or make the table hidden.
Re. #2
You could use a listbox (basically the same idea as a combobox).
You could include the lookup table in the underlying query, but then there is more danger of the values getting changed, which is exactly what you were worried about in the first question.
Stick with the combobox.
You can create different versions of a form. One might have Allow Edits, No, another might be Data Entry, Yes, meaning that it can only be used to create new records.
However, suppose someone is creating a new record and they select the wrong FK by mistake. How can they correct this? You could use VBA to produce a confirmation dialog in the first instance, and perhaps an Undo button where VBA would deliberately perform the Undo. Access 2010 also has Data Macros (equivalent to triggers) that you might use to store the old and new values, and other information, when a user changes a FK value.
Access does not implement user-level security, so the user can still open and change data in the raw-data tables. You should, however, have enforced referential integrity on the table-join, so that a user cannot enter a FK that doesn't already exist as a PK in the related table.
In summary, you could add additional columns to the combobox to help the user select the correct item, and you might consider an additional confirmation dialog (a MsgBox) before a record is saved into the data-table. But you cannot prevent people from making mistakes. (Enforcing Referential Integrity will prevent nonsense data from being entered.)
Second question:
A combobox (or possibly a listbox) is the easiest way for users to enter a FK value, without relying on memory. An alternative would be to use a button (or other control and event) that opens a secondary form. This form might have some filtering features to help the user find the correct FK value. When this form is closed you would then need to write some code to update the relevant control on the main form.
Related
I have a parent form (frmGroupSession) that has a subform (SubFormParticipants) in datasheet view. The subform is based off a query that selects all participants ([CLIENT ID], [NAME], [ATTENDED]) that had attended a specific group [GroupID] on a specific date [GroupSessionDate]. The parent form saves to a table that logs group sessions (tblGroupSessionLog). I need to save the group's participants [CLIENT ID] to the record within tblGroupSessionLog
Basically, I need to pass data from the subform to the record within tblGroupSessionLog. I'm not sure what the most effective way to do this, if it's possible at all. Ideally, I would like to have each unique participant [CLIENT ID] stored in its own field within tblGroupSessionLog. If there were 20 participants in the subform then each row value from the first column/field [CLIENT ID] would be passed to the corresponding field within tblGroupSessionLog ([ClientID1] thru [ClientID20])
I am relatively new at this. Even asking the question was difficult.
I am not sure what else I can provide to help you wizards with the solve, but let me know and I will.
Thoughts? Ideas?
Access 101 : You have a many to many relationship You should look that term up but in short it means clients can belong to many groups and each group can have many clients. (so bang your data into a normalized structure similar to the following:
First tip make sure to add the relationships under database tools (you should look that up). Access needs to know how the tables are related to manage the keys behind the scenes and sometimes access makes better decisions about automatic form creating when it already knows the relationship structure. Once your data is properly structured access makes it easy to produce functional if much less than styling data entry forms which can also be used as even worse search forms. For instance Click on any table and hit create form on the ribbon and access will create the data entry form form you.
Basic Style tip 1: Always delete primary key fields like ClientID from the form. The field is still there in the form's record source being managed by access. Users almost never need to see any table keys. This gives you a basic data entry form which you can also use to scroll through any clients you have entered using the record selector circled at the bottom of the frmClients.
Play around with the record selector to see how it works. In particular go past the last record and you will find you can enter new clients and access will automatically give them a ClientID. You can also cycle through your Clients and update them using this form it just isn't stylish. In the same way we can make a form for the groups table.
You make a form for the frmGroupSessions table in the same manner as the others but add a step. Replace the text boxes holding ClientID and GroupID with human readable comboboxes. Here is a link to help with that: https://www.google.com/search?q=access+change+text+box+to+combo+box&oq=access+change+text+&aqs=chrome.0.0i457j0l2j69i57j0j0i22i30l2.7503j0j1&sourceid=chrome&ie=UTF-8#kpvalbx=_r0sFYJ7vBcfY5gLz2aTgBw15
Becomes:
At this point play around to learn. Use the Record Selector at the bottom of frmGroupSessions to add and modify data. Play with the Tables and see what happens. Start messing with the form properties in particular the default view. Soon you will have ideas about how the form could be better and you can start figuring out how to style them.
I have an access database that holds medical information. It holds quite a bit of information so i have grouped like fields together into individual tables and linked them using a common primary key. I have created a tab style form with subforms on each tab.
Some of these subforms contain fields from only one table, however there are a few subforms where i have included fields from more than one table.
For example, i have a table that holds blood transfusion data and a table that holds patient characteristics. Some Fields from the blood transfusion table and patient characteristics table are in the same subform, but I also have fields from both these tables in other subforms.
When i try to insert data into the sub-forms with fields from multiple tables i get the following errors..
update or cancelupdate without addnew or edit
and
The changes you requested to the table were not successful because
they would create duplicate values in the index, primary key or
relationship. Change the data in the field or fields that contain
duplicate data, remove the index, or redefine the index to permit
duplicate entries and try again.
From researching the problem i gather this is because access is trying to create a new record for both tables, but if a record has already been created with that primary key (from inserting data into a previous subform) it won't edit the existing record.
Does anyone know how to get access to edit the existing record in this instance instead of trying to add a new record? I have basic skills in VBA but this is a bit past my level of experience.
Any suggestions would be greatly appreciated.
I used have a whole long response about split forms instead but I was having a horrible time getting it to work. So here is my new and improved answer for using subforms.
Here is a link with sub form info if you want to brush up for your purposes https://support.office.com/en-us/article/Create-a-form-that-contains-a-subform-a-one-to-many-form-ddf3822f-8aba-49cb-831a-1e74d6f5f06b
Step 1
Make sure your main form is bound to the right table.
For my purposes I used a single combo box on my main form to search with. Make sure all the field parameters on your combo box are correct. This includes making sure the Row Source is correct and that you DO NOT have a control source entered.
Step 2
Don't press enter after making a selection in the combo box. To prevent people from hitting enter I created a dummy button at the bottom that says "Save and Refresh" but all it does it create a message window that pops up with "Save Successful". I find hitting enter creates the first error you keep getting. I'm not sure how to address this in a more sophisticated way yet.
Anything else that comes up I will add later.
In one of my access forms I use a continuous sub form with just one field per line that creates an entry in a junction table.
While creating and changing entries in the junction form works fine, I have problems removing those entries. When I clear a line in the sub form, the entry should be deleted. Instead I get an alert message "Null value in index or primary key not possible".
I think I need some vb-programming to solve that problem, right? What would be a propper approach for that?
(I don't use MS-Access regularly so maybe I misused some technical terms. Please be kind.)
[edit]
I now use a delete button instead. I leave the topic open for the moment just in case somebody wants to add an answer.
Since you are (assumingly) using bound forms, every entry on your form is directly written into the table. Since your primary key is not allowed to be Null, it immediatly presents you with the alert.
There are different ways to solve this problem, depending on your goals.
If you want to allow empty entry's in the field that's momentarily your primary key, you should remove the key in the design view of your table.
If you want to disallow the empty entries, but want a custom error message or the message to appear after clicking a save button, you should change to an unbound form.
We are rebuilding an asset database with Access 2013. We have 1 table with a Primary Key (Serial number of asset), and 22 other fields. We're designing a form to be used with the table so that we are not manually editing the table. The 'Status:' field explained later does not exist in the table; it is a user friendly way to show if the record exists or not.
The end goal is to have a form that will two cases. A user will enter a PK and hit the tab key. Then:
If the PK exists, it will pull the info from the other 22 fields and put them into the fields on the form (1:1) and update 'Status:' to 'Existing'.
If the PK does not exist, it will change the 'Status:' to 'New' and make all of the fields blank.
Most of the fields on the form will be Combo boxes. There will be a couple text fields and 1 date/time field.
Once a user is done with the form and has made any necessary changes, there will be a 'Save' button at the bottom that will write whatever is in the forms to the row indicated by the PK.
I have found partial solutions with the LostFocus() event in Access 2013 on the PK field of the form. I have little experience with MS Access, moderate experience with DBA, and no experience with VBA programming. I'm sure this solution can be done, my question is: can it be solved in a way other than hard coding the solutions? I also looked around for form building, but I couldn't find anything that worked how we need it so if there is a tool that can accomplish this, that is acceptable.
You might consider a form that contains a subform. Basically, you would design a form that has your PK input box and a subform. When the user hits tab (or a "Search" button), a query would run to search the table and display that record in the subform, or you could insert a new record if not. You may need to use a few queries and macros to link it all together, but it can be done code-free.
I have an Access database that is used to store basic info in a table such as first and last name. How would I go about adding the functionality to lookup by last name?
Is there a way to type in the last name and then hit like F12 or something like this? Can someone please point me in the right direction or provide me a link?
SELECT tblPatient.LName AS [Last], tblPatient.FName AS [First]
FROM tblPatient
WHERE (((tblPatient.LName)=[Enter Last Name]));
How do I tie this into my form now?
I'd suggest you create a form, with a textbox 'search' at the top, then either a listbox or subform below to display results.
The listbox record source would be:
SELECT tblPatient.LName, tblPatient.FName
FROM tblPatient
WHERE tblPatient.LName LIKE Forms!myForm!search & '*';
You can either add a Search button, which requeries the listbox, or do the requery via the Change event of the search textbox. The later may be slow if you have a large number of records; if that's the case, you could check that at least 3 (?) characters have been entered before calling the requery.
You just need to create a query in which you put =[?] as the "last name" value.
When you open that view, you'll be asked to type in a lookup value for that field.
Not sure if this is what you are trying to archieve, though...
This is probably a bit overkill for what you want to do, but I assume that you want to perform a search by last name. You should be able to glean the information you need from this article:
Build a search criteria form
http://www.everythingaccess.com/tutorials.asp?ID=Build-a-search-criteria-form
You can create queries in Access if the user you're targeting with the searchability has Access themselves.
From the main Access UI (assuming Access 2007), go to the Create tab and then select the "Query Wizard." Here is an article on the subject.
Otherwise you can create a program and connect to the MDB/ACCDB file running the query programmatically.
Seeing you wish to look up a name and populate the form based on the name selected, I suggest you need a combobox. There is even a wizard for doing exactly what you want. To start, you will need a form bound to a table or query, that is a form with a Record Source.
Add a combobox to your form
Select :
Find a record on my form based on the value I select in my combobox
Select the ID (primary key), Last and First name fields.
Access will display an example, suggesting that you hide the Key (id) column. Accept this.
Choose a name and finish.
There are a few other small things that could be done for neatness, but you will end up with a form that find the record you want. In addition, the combo will autocomplete if you type in a few letter.
If this is an mde, which your subsequent post seems to suggest it is, there is little you can do wuth out the original file. However, you could try opening the database while keeping the shift key held down and see if that allows you to edit. If you cannot get the original and the shift does not work, you could try rescuing the data, if it, too, is stored in this file.