T-sql is not null or empty

But so what, it was still worthwhile! When we say whitespace, we always mean more than spaces. Here is a demonstration:. One would have to use the LEN function to tell them apart. You are commenting using your WordPress. You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account.

Notify me of new comments via email. Notify me of new posts via email. Enter your email address to subscribe to this blog and receive notifications of new posts by email. Email Address:. You could use isnull function to get both null and empty values of a text field:. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 8 years, 9 months ago. Active 5 months ago. Viewed k times. Improve this question. This question does not show any research effort. It is important to do your homework. Tell us what you found and why it didn't meet your needs. This demonstrates that you've taken the time to try to help yourself, it saves us from reiterating obvious answers, and most of all it helps you get a more specific and relevant answer.

Add a comment. Active Oldest Votes. Improve this answer. It's said that they both use the index on 'col' and do an index seek. Uwe Keim Sameera R. Oracle's NVL var1, 'value' will take care of empty string ' ' replacement. T-SQL's Isnull var1, 'value' doesn't. Praveen Nambiar Praveen Nambiar 4, 1 1 gold badge 20 20 silver badges 31 31 bronze badges. Prior to the addition of error handling, a blank value was used to represent both null values from databases and error values.

Error handling separates these two interpretations of blank which could change the behavior of existing apps that continue to use IsBlank. The return value for IsBlank is a boolean true or false. The Coalesce function evaluates its arguments in order and returns the first value that isn't blank or an empty string. Use this function to replace a blank value or empty string with a different value but leave non- blank and non-empty string values unchanged.

If all the arguments are blank or empty strings then the function returns blank , making Coalesce a good way to convert empty strings to blank values. Coalesce value1, value2 is the more concise equivalent of If Not IsBlank value1 , value1, Not IsBlank value2 , value2 and doesn't require value1 and value2 to be evaluated twice. The If function returns blank if there is no "else" formula as is the case here. All arguments to Coalesce must be of the same type; for example, you can't mix numbers with text strings.

The return value from Coalesce is of this common type. The IsEmpty function tests whether a table contains any records. It's equivalent to using the CountRows function and checking for zero. You can check for data-source errors by combining IsEmpty with the Errors function. The return value for IsEmpty is a Boolean true or false.

At this time, the following example only works for local collections. We are actively working to finish this feature and complete the separation of blank values from errors. Set the button's OnSelect property to this formula:. The Cities collection appears, showing one record with "Seattle" and "Rainy":. Add a Label control, and set its Text property to this formula:.

The label shows false because the Weather field contains a value "Rainy". The Weather field of the first record in Cities is replaced with a blank , removing the "Rainy" that was there previously. The label shows true because the Weather field no longer contains a value. Add a label, and set its Text property to this formula:. By default, the Text property of a text-input control is set to "Text input". Because the property contains a value, it isn't blank, and the label doesn't display any message.

Because the Text property no longer contains any characters, it's an empty string, and IsBlank FirstName. Text will be true. The required field message is displayed. For information about how to perform validation by using other tools, see the Validate function and working with data sources.