Create a comma separated list from column using select statement

Q: In SQL Server how do I convert a column into a commaseparated list

divIn SQL Server use the STRING_AGG function with the column you want to concatenate amp the delimiter a commadiv

Q: Can I create a commaseparated list without using STRING_AGG

divYes you can do this by using the XML Path concatenation method or recursive CTEs to concatenate items with custom logicdiv

Q: What happens if I wish to exclude NULL values from the commaseparated list

divTo exclude NULL values just use a conditional statement within the aggregation function like this STRING_AGGcolumn_name WHERE column_name IS NOT NULLdiv

Q: What happens if I wish to exclude NULL values from the commaseparated list

divTo exclude NULL values just use a conditional statement within the aggregation function like this STRING_AGGcolumn_name WHERE column_name IS NOT NULLdiv

Q: Is there a maximum amount of values I may concatenate into a commaseparated list

divThe STRING_AGG method in SQL Server has a maximum input size limit of 4 MB therefore the number of items that can be concatenated is determined by the size of the datadiv

18 Feb 2025

Intermediate

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1 min read

Create a comma-separated list from the column using the select statement: An Overview

Sometimes it is necessary to construct a comma-separated list of column values, such as a list of EmailIDs for mail distribution. In SQL Server, this can be accomplished by using COALESCE, as seen below. Consider using a SQL Server Tutorial or enrolling in a SQL Server Certification Course to gain additional insights and skills.

Read More - SQL Interview Questions And Answers

Use of COALESCE to create a comma-separated list

Suppose we have the following data in the Employee table and we need to make a semicolon-separated list of EmailIDs to send mail, then we can use COALESCE as shown in below fig.

Here I am creating a semicolon(;) separated list. You can use a comma(,) in place of the semicolon to make the comma-separated list.

For SQL Server database mail setup and configuration and more on how to send mail from SQL Server database you can refer to this article.

Summary

In this article, I expose the use of COALESCE to make comma-separated or deli-meter-separated lists. I hope after reading this article you will know how to configure SQL Database Mail in Sql Server. I would like to have feedback from my blog readers. Please post your feedback, questions, or comments about this article.

FAQs

In SQL Server, use the STRING_AGG() function with the column you want to concatenate & the delimiter (a comma).

Yes, you can do this by using the XML Path concatenation method or recursive CTEs to concatenate items with custom logic.

To exclude NULL values, just use a conditional statement within the aggregation function, like this: STRING_AGG(column_name, ',') WHERE column_name IS NOT NULL.

The STRING_AGG() method in SQL Server has a maximum input size limit of 4 MB, therefore the number of items that can be concatenated is determined by the size of the data.