Want to know more about the COALESCE Empty String in SQL Server? Then this article is for you. As part of our Microsoft SQL Server Support Service, Bobcares provides answers to all of your questions.

COALESCE Empty String in SQL Server

The COALESCE function in SQL Server is utilized to return the first non-null expression among its arguments. When dealing with empty strings (”) and null values, COALESCE sees an empty string as a legitimate value, therefore if it’s the first non-null argument, it will return an empty string. Using empty strings, COALESCE operates as follows:

In this case, COALESCE returns the first parameter ” even though it is an empty string because it is regarded as a valid value. We must use the NULLIF function in conjunction with COALESCE or other conditional logic if we want to handle empty strings differently and treat them as null values. For e.g.,

As a result, the initial NULLIF in this case returns NULL, and COALESCE then returns the first non-null value among its inputs. In this case, NULLIF(”, ”) effectively converts an empty string into a null value.

The COALESCE function in SQL Server is used to retrieve the first non-null value from a collection of expressions. The COALESCE function, however, regards an empty string (”) as a valid non-null value. Before using COALESCE, empty strings can be converted to null using the NULLIF function if we want COALESCE to consider them as such and ignore them. Based on the unique requirements, this enables us to handle empty strings in SQL queries effectively.

[Looking for a solution to another query? We are just a click away.]

Conclusion

To conclude, the article went over the details of the COALESCE function handling Empty Strings in SQL Server.