Article by Jeevan A Y. Please select the batch. Cookies help us provide, protect and improve our products and services. By using our website, you agree to our use of cookies Privacy Policy. It would help to know the context of your question. If you have a specific table in mind, and you want to see all the rows that contain any null columns, then you can easily build a query to return them.
But you have to name each of the columns in the table. For example,. Column4 Is Null. On the other hand, if you don't have a specific table in mind, but need to be able to query any given table, then you might need VBA code to examine the table structure and get a list of all the fields so you can build a SQL statement such as the above using the correct field names.
Or, you might be looking for code on a form that prevents a record from being saved if all or certain fields are null. That would be yet a different situation, and would probably be solved with a VBA event procedure in the form's BeforeUpdate event. And of course you can set the Required property to Yes for each of the fields in the table's design.
That will prevent any record from being saved that doesn't have a value in every field, and will raise an error any time the user attempts to save such a record. You talk about presenting the information to the user.
Under what circumstances would you be wanting to do this? What would be the trigger for the examination? And thanks for your attention! Might be the case that I dont understand the meaning of "required" property and how Access handles it in case of an error. The error message I get is attached below. If I click yes i get null values in the column I for test purpose defined as integer, but all other records are inserted. Is that as expected? This is strange to me as the error message says records are set to null.
Active Oldest Votes. Ken White Ken White k 13 13 gold badges silver badges bronze badges. Thanks for the tips and the code change. I replaced the existing code, however when I do have a BU Selected, meaning it is not null, nothing happens still. I like this as the answer, it is more elegant and avoids ExitSub. I try to avoid that as much as possible, I don't know why, it just seems like cheating to me.
This answer is completely readable, and as simple as possible. Just what one would expect from a professional stand point. That is my opinion. It's also the way I would have written it. Sign up or log in Sign up using Google. The basic variable types all have a default value, a String is of zero length "" from the moment the variable is declared - it has no uninstantiated state.
You can also test for vbNullString. So if you're trying to test whether anything has been assigned to a String variable the only things you can do are:. As others have noted, you want to test against the null version of a string, vbNullString, and not against Null specifically.
In addition to this, you also need to make sure your object isn't null itself. For example:. If this is the case, then the below pattern would be preferred:. In this way, we are only ever calling upon the text property of the Attribute if we have actually set the Attribute. This avoids errors down the line. Finally, if you want to figure out what is happening in the code that is causing both if's to run, do something like this:. Otherwise use "Null" if actual string value. You can also use an If-Then-Else construct, particularly if you have other actions you want to perform at the same time.
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