9/10/2023 0 Comments Sql less than or equal toIn this case, we are converting the DateJoined value to a simple date (day, month, year without the time). This is the way SQL Server works with NULLs.With dates, you will frequently want to use a bit more complex structure for the comparison to work correctly. I would continue to do explicit null checking on columns that could possibly be null, sure it doesn't look the best but it works all of the time.ĪNSI_NULL set option will work for now but NOT a good idea especially if you don't control the environment, plus it will be forced set ON later and cause errors where you'll need to re-write your application logic anyway. I don't know the end-game per-se and writing your own dynamic querying tool is quite the deat when the logical consistencies are all factored in (such as this). You could also have options such as "This column may be null, do you want those values?". What your designer could do is check to see if that column could even be null and if so the appropriate logic could step it and create the correct query. I'm not saying it's a super awesome and great idea but it works all of the time. Why? Well because with a schema that allows nulls, that's the way to do it. I get what you're trying to do, and to make a counter point I would ask if you've seen any queries generated by reporting services or something like Cognos? If so, you'll see exactly what you're describing you don't want to do. There is a session setting called ANSI_NULLS that could make your queries behave as you would like them to, however, it's deprecated and will be forced to ON (which you don't seem to like) in a future version: To start off, NULL does not mean "no value" it means "Unknown value" in SQL Server. and then click a button to view the results of that request. I just want you to pick a table, choose some fields to filter on with equals, not equals, in, not in, etc. My program is table-definition-agnostic meaning I don't care what's in your table and don't want to know what your table's definition is. The fields chosen by the user can be any and/or all fields in a given database and if I have to literally put that ISNULL check on every single field that would be really inefficient and make looking at the SQL super ugly. I am writing a program that let's you build queries to database tables and let's the user dynamically create filters and such which essentially at the end of the day constructs a SQL statement and gets the results to display to the user. My real problem of why I don't want to do it the way I showed was not exposed. Also turning off nulls on my tables is definitely not an option. Seems logical to me.ĭoes anyone know how I can, in a cleaner way, include nulls in my results when using comparisons without having to include an explicit check each and every time. I mean I know NULL is not a value and thus can't be compared but can't you infer that it is, in fact, definitely not 26? If 26 is something and NULL is nothing and nothing is not something then NULL is not 26. I understand I can do the following as a workaround but seriously? Having to add parentheses and check if is null for every single field every single time I want to include it? Seems ugly, not intuitive and crazy. So basically in SQL Server a NULL means there is no value and thus can't be compared which returns some unexpected results.įor example, the following query doesn't return rows where value IS NULL but I want it to: SELECT *
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