SQL Server has two great methods for grouped concatenation: STRING_AGG (), introduced in SQL Server 2017 (and now available in Azure SQL Database), and FOR XML PATH, if you are on an older version. The STUFF function starts at position 3 and runs for 5 more characters. The inner command is FOR XML in its simplest form, with a comma added to the selected data: This is a very simple example of the XML command. Note: The name of the child nodes has changed based on our select statement: In SQL, when you perform any kind of aggregation or selection function to a column, it no longer applies a default name. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. The only difference is the number of characters specified to delete via the delete length parameter. It helps consolidate data for reporting purposes. The main idea around the SQL Server function called STUFF is concatenating multiple columns into a single column with more flexibility than the CONCAT function would provide. I am taking column values that are split into multiple rows and concatenating them, but have come across an issue where the text field is getting concatenated for more than 1 WAPROC code. , CourseName There is only ONE record but 31 fields. This is incredibly wasteful. LEFT JOIN #StudentCourse sc ON sc.StudentID = s.StudentID power bi Distributed Availability Group Across Different Domains, Creating an Availability Group Listener Basic Example, Upgrading A SQL 2012 AG to 2017 Without Downtime, Upgrading SQL 2012 AG to SQL 2017 the fun to be had with SSRS. [user] for XML PATH (''),TYPE). Women are also in business, so it is important for them to have a competent resume, for this I advise this site https://www.insightssuccess.com/resumes-tips-for-women-in-business/, because there you can learn about Tips for writing a resume for women in business, https://essaysrescue.com/edubirdie-review/, https://www.insightssuccess.com/resumes-tips-for-women-in-business/. Sorry, your blog cannot share posts by email. , s.FirstName This trickery actually works out to have an advantage because we need to concatenate our strings with a comma to create a comma separated list of values. Very helpful breakdown, Awesome and very useful explanation. Send your offers and ideas to [emailprotected]and we will get back to you at the earliest opportunity. oracle Making statements based on opinion; back them up with references or personal experience. , LastName NVARCHAR(50) NOT NULL In this example, the first character of the original string is replaced by the 1st character, and the last one is replaced by the 7th character. To learn more, see our tips on writing great answers. However, this type of analysis is pretty common in database reporting architecture. ) SELECT s.StudentID DROP TABLE IF EXISTS #Students Comma Separated Values using the FOR XML PATH clause, , ICS140, ICS225, ICS240, ICS310, ICS240, ICS310, ICS140, ICS225, ICS140. , CourseCode NVARCHAR(50) NOT NULL VALUES (10001, N'Bob',N'Roberts') Ill do everything on SQLFiddle. SQL Server provides solutions for dynamic data masking. Why does the USA not have a constitutional court? As demonstrated with FORXML and STUFF, T-SQL offers the ability to consolidate data into single columns with some sort of primary identifier. FOR Xml Path ('')),1,1,'')) AS Cities From #tempCityState t -- or tentatively --Select Distinct State, (Select Substring ( (Select ',' + City -- From #tempCityState -- Where State = t.State --. For example, computed columns or nested scalar queries that do not specify column alias will generate columns without any name. query performance , (10001, 310) The top-level FOR XML clause can be used only in the SELECT statement. Since 8 is more than the original string length of 7, the value is returned as ABXXX. It deletes a specified length of characters in the first string at the start position and then inserts the second string into the first string at the start position. FOR XML PATH ('') is used in older versions of SQL server (pre 2017) to get values from multiple rows into one. Mathematica cannot find square roots of some matrices? Why is the federal judiciary of the United States divided into circuits? ) Here is a data diagram that represents our sample dataset. Why would Henry want to close the breach? Here is the final query that will return the result with a comma separated list in the result set. It only takes a minute to sign up. SELECT * FROM ( -- ) 1 solution Solution 1 Something like this should work: SQL Expand Anith Sen gives a summary of different . Thus, when you are using the STUFF command, you are rearranging the column data. However, STUFF could be used to obfuscate sensitive data when it is displayed. , (10004, 225) FOR XML PATH('')),3,1000) Consequently, the data is just stuffed into the Person Element. SELECT ', ' + c.CourseCode , s.LastName We can use XML PATH and come up with the solution where we combine two or more columns together and display desired result. LEFT JOIN #StudentCourse sc ON sc.StudentID = s.StudentID , Courses = ( , s.LastName In this article, well explore the possibilities that the STUFF command provides for SQL Database specialists. , (10001, 240) With these, its easy to do these, SQL Server CASE expression is very useful in returning an output based on some conditional matching criteria. For example: Using a solution I found on Stack Overflow: Are there any better solutions? The annotated part means that you either have to provide a summary https://essaysrescue.com/edubirdie-review/ of the document in question or you have to assess the work in relation to your specific topic and research. VALUES (140, N'ICS140', N'Introduction to Programming') sql query Lets take the following table structure: Suppose you would like a report with 2 columns. I am able to achieve this using STUFF and FOR XML PATH using the below query. ) GO mysql By removing the explicit namimg, SQL isn't able to guess the column name. Here comes some more trickery, if we concatenate a string and do not provide an alias, the column name is undefined and thus is empty. Build the table structure and insert data: In this example, an inner query is joined to each USER_ID. azure The Path mode with FOR XML in SQL Server returns a result set as the XML element. The following query will start at position 1 and replace the 1st character with '': Finally, well take the whole query and make sure its of type VARCHAR. Its an interesting solution that is often shown to people who need such a thing and is far faster than other solutions Ive seen. This can be accomplished by: The solution proposed in this tip explores two SQL Server commands that can help us achieve the expected results. Thank you. Rolling up data from multiple rows into a single row may be necessary for concatenating data, reporting, exchanging data between systems and more. .net framework by executing a query using a "pivot xml" instruction, I get the following XMLType result: (The number of <item>s is unknown, it depends on the result of the originating query). CourseID INT PRIMARY KEY NOT NULL sql Your email address will not be published. ssms Specify the column names in the XML path query, create table customer (cid int identity(1,1),cname varchar(10)) insert into customer values ('test1'), ('test2') DECLARE @str varchar(4000) SET @str = (SELECT cname+',' FROM customer FOR XML PATH('')) SET @str = SUBSTRING(@str,1,LEN(@str)-1) SELECT @str Thanks Sarat full-text search This functionality is great if you need to return the delimited list through a function or persist into a variable, however what if you need to return a comma separated list in a result set? Besides, STUFF can be combined with other techniques for some interesting effects. So running the following query will give us all of the values in a comma separated list. Thanks for contributing an answer to Database Administrators Stack Exchange! The STUFF command is used to replace the initial comma. So the idea for this blog post is that we take a list of students details and include a comma separated list of the course codes that they have registered for. It is because FOR XML path mode treats column names and alias names as the XPath expression. How do you go about producing a summary result in which a distinguishing column from each row in each particular category is listed in a 'aggregate' column? WHERE s.StudentID = sc.StudentID The query is in an in-line TVF, so I cannot use a temporary table. By selecting the result of the entire query, we transform the XML into a value: To remove the leading comma, well use STUFF(character_expression, start, length, replaceWith_expression). SELECT Surname. However for the following test data (1000 ids with 2156 rows per id for me). The execution plan I get for the query in the question first does the concatenation for every row in the outer query and then removes the duplicates by id, SomeField_Combined1, SomeField_Combined2. Written by Ian Fogelman June 16, 2021 LEFT JOIN #StudentCourse sc ON sc.StudentID = s.StudentID Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. indexes AWS DROP TABLE IF EXISTS #Courses Required fields are marked *. Again, storing your results in a temporary table is a good idea. database backup The best answers are voted up and rise to the top, Not the answer you're looking for? sql server 2019 sql operator We are going to use the FOR XML clause, however we are going to pass an empty string to the PATH function. . The XML option to transposing rows into columns is basically an optimal version of the PIVOT in that it addresses the dynamic column limitation. Im not a big fan of XML via T-SQL far too long-winded a monster for my liking. Why is there an extra peak in the Lomb-Scargle periodogram? like. linq QGIS Atlas print composer - Several raster in the same layout. From the FOR XML PATH documentation: Any column without a name will be inlined. stored procedure Your annotated bibliography is far more than just a simple list of references listed out to detail the author, the title and so on. Always On , (10003, N'Tom',N'Tompson') linked server If we nest the query with the FOR XML clause in a sub query and reference the student id from the outer query, this will limit the comma separated lists to only the course codes that are linked to the students. I could add as many tags as I wished to do so by . Save my name, email, and website in this browser for the next time I comment. Starting from that result, I need a result with one row and as many columns as the items. FOR XML PATH; Thank you very much! Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Besides, STUFF can be combined with other techniques for some interesting effects. One-Row Multiple-Columns from an XML text. Across all major RDBMS products, Primary Key in SQL constraints has a vital role. The first one is the output from the STUFF command the original ABCDEFG string will be stuffed with the XXX string. FOR XML PATH(''); Being that we were able to remove the root node by simply renaming the node, we need to do the same for the column name CourseCode. You can follow along by starting your own fiddle or clicking the results link for each step. A CLR aggregate will almost certainly be the fastest way of doing this. Notify me of follow-up comments by email. Help us identify new roles for community members, Create hierarchy of multiple levels where each node has a random number of children, Query with join and concatenation of one joined table's column, Giving EXEC (@Variable) a Column name and Concatenation, Are multiple column index used in single column where clause. Change the command to add a comma between each surname and remove the element name (the 'test') and you get a strange XML value like this: Microsoft Azure GO json The view could use the STUFF command to mask everything except the last 4 digits of the SSN. Why is Singapore currently considered to be a dictatorial regime and a multi-party democracy by different publications? , (10004, N'Rich',N'Richardson') Please comment with other use cases for the STUFF command. What we would expect the script to return is a result set with student details including a comma separated list of courses that looks like this: Using the following temp table structure and sampling of student and course data gives us the data that we will need for this example. In the table below the WATEXT field should be concatenated for the first 2 rows where the WAPROC code is 36812-00 but I am getting the WATEXT from all 4 rows . sql constraints Database development, Statements, October 20, 2021 LEFT JOIN #Courses c ON c.CourseID = sc.CourseID sql server 2016 , (10002, 310) 08:45 This time I have added the comma (',') which causes the result set have returned column without a column name. , CourseName NVARCHAR(50) NOT NULL This blog post will look at, and describe, how to build out a delimited or comma separated list using FOR XML PATH clause. SELECT ', ' + c.CourseCode .net I still found Kenneth's solution with two XML PATH calls much faster and less resource intensive. The inner select comes from an expensive multi-table join (not the single table 'test' shown above). FOR XML PATH(''); So now we have all of the course codes in one big comma separated list, we need to get them into sub lists for each student. Use Right function to remove the leading comma instead of xml functions, Use case statements to avoid comma for blank spaces, Note: Here Group by can be replaced by distinct as well since we are not using any aggregate functions. You can test this by running both queries, the first query will have a root node of whereas the second query only returns the nodes. WHERE s.StudentID = sc.StudentID with data from the tblValuationSubGroup table. The trick involves using FOR XML PATH('') to build multiple values and then cast them back into a single string. FROM #StudentCourse sc JOIN #Courses c ON c.CourseID = sc.CourseID , (10005, N'Will',N'Williams'); Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. When columns are selected, those are used by default, however you can manually give any column a specific name. GO If it works stuffing 1 column into another, but not with more than 1, then you probably need to do multiple subqueries all enclosed in the main SQL statement; similarly to a CTE. , CourseCode They have different performance characteristics and can be sensitive to minor syntax details, and I'll deal with those differences as we go along. What i did is I put the expensive query in a cte and did the the same you did. , Courses = SUBSTRING(( FROM #Students s INSERT INTO #StudentCourse (StudentID, CourseID) Thus, when the delete length parameter from the starting position parameter is longer than the original string, the data is truncated. However, there is no denying the usefulness of it and the fact that on occasions it simply doesnt matter if you like an aspect of SQL Server, you may simply have to learn to use it. GO replication Unlike other XML modes, this FOR XML PATH mode provides control over the generated XML file. By manually specifying the path as an empty string, all the data elements are shown right next to each other. t-sql STUFF can also be combined with other SQL Server functionality like ForXML. Two problems solved with one command. t-sql statements , (310, N'ICS310', N'Database Management'); A simple, and intuitive way of displaying data is surprisingly difficult to achieve. In Management Studio you should see something like this (No column name). We demonstrated both simple and complex examples of the STUFF command and listed a few use cases for which STUFF can be applicable. Adventure works example.Previous video uses coalesce: https://www.youtube.com/watch?v=1kfp0s-lc3M From the FOR XML PATH documentation: Any column without a name will be inlined. CREATE TABLE #StudentCourse( Your email address will not be published. SELECT c.CourseCode tools Design by StylishWP. , s.FirstName In this example, it was the USER_NAME. sql functions FOR XML PATH ('') Code. Imagine a view sitting on top of a table that has customer PII fields such as SSN. Database development, Statements. execution plan The replacement happens at the third character of the original ABCDEFG string in every execution. Option #3: XML. You can put ORDER BY Column_ID right before FOR XML PATH('') to enforce the desired order. transaction log. ForXML is a feature in SQL Server that can transform the result sets of SQL queries into XML formatted results. Is this an at-all realistic configuration for a DHC-2 Beaver? power bi reports FROM #StudentCourse sc JOIN #Courses c ON c.CourseID = sc.CourseID Other technologies and concepts that Ian has expert level experience with include AWS, ETL strategies, Python scripting, Cloud architecture and system automation. Does integrating PDOS give total charge of a system? The main idea around the SQL Server function called STUFF is concatenating multiple columns into a single column with more flexibility than the CONCAT function would provide. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Did neanderthals need vitamin C from the diet? SELECT a. FROM #Students s How to concatenate multiple columns in to a single row? In some ways it seems like it should take longer but it doesn't. The command weve been using all along is FOR XML which has four different modes: In this case, were using PATH, which will wrap the data elements in a parent element named for the table from which it came. September 28, 2022 Counterexamples to differentiation under integral sign, revisited. We use the FOR XML PATH SQL Statement to concatenate multiple column data into a single row RAW Auto EXPLICIT PATH Example 1: Basic use of the FOR XML PATH clause Let's use the WideWorldImporters sample database for this part of the article. This will rename the XML root node as an empty string, thus not returning a root node. , FirstName NVARCHAR(50) NOT NULL Would it be possible, given current technology, ten years, and an infinite amount of money, to construct a 7,000 foot (2200 meter) aircraft carrier? With an index on the ID column. Change the command to add a comma between each surname and remove the element name (the test) and you get a strange XML value like this: The next requirement is to remove the leading comma and convert this back to a character field. Now that we have our dataset, lets turn our focus on creating the comma separated list of course codes. The last trick: If you specify a zero-length string, the wrapping element is not produced. StudentID INT NOT NULL A curious endeavor to catalogue and document the wealth Consequently, the data is just stuffed into the Person Element. oracle analytics sql server rev2022.12.11.43106. How could this be accomplished in pure T-SQL? How is Jesus God when he sits at the right hand of the true God? , (10005, 140); We are going to start out by creating a simple query that returns all of the data we need, to generate the output. However, you should consider how it affects the production level queries. ssis I am using 4 different SELECT statements for each of the categoryies. tips and tricks , CourseID INT NOT NULL VALUES (10001, 140) In a previous post we looked at how we can build out a delimited list using the ISNULL and COALESCE functions. If you need help with that, drop me an email and I'll be happy to help. In this case the first parameter for STUFF is the XML query. (SELECT ',' + UR.ROLE FROM #USER_ROLES UR WHERE UR.USER_ID = U.USER_ID FOR XML PATH . sql database Thank you So much for your expalanation:). [user] result: user | group a admin,test,edit b read,write c read,write but i need this Post was not sent - check your email addresses! NOTE: This is a very important step towards concatenation. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. FROM #Students s; Your email address will not be published. CodingSight is open for new authors and partnership proposals. I ran this version which is the version I first learned. As STUFF returns character data or binary data depending upon the data type it is processing, in this case it returns the result as a character field, with the leading comma removed. There are other ways to do this and other customizations you can add to this query, but this should help you understand a little bit more of the fundamentals underneath it all. Using tricks with the FOR XML PATH clause, a correlated subqueries, and un-named columns will give us all the tools needed to return a delimited list within a result set. SELECT s.StudentID, s.FirstName, s.LastName, c.CourseCode The following rewrite avoids this. Ian is a database enthusiast with expertise across multiple database technologies including SQL Server, RDS, Snowflake, MySQL and Postgres. Required fields are marked *. azure sql For each distinct id in #test it performs two operations instead of one but this operation is significantly cheaper than constructing the XML and then reparsing it. You can nest the STUFF command within another STUFF command and utilize it as many times as needed. Also, for good measure, well give the returned column a name: And thats how to go from constructing XML to a relatively simple concatenation. As a result, we have a nice comma-separated list of each user with the respective roles. The first column is USER_NAME, and the second is a comma-separated role column for each role the user holds. LEFT JOIN #StudentCourse sc ON sc.StudentID = s.StudentID I ran a few tests using a little over 6 mil rows. Can it all be merged into one? How to make voltage plus/minus signs bolder? Lets first take a look at the official Microsoft definition of the STUFF function: The STUFF function inserts a string into another string. As an intermediary step, well explicitly specify a name just to show that the comma itself isnt modifying the result set: By removing the explicit namimg, SQL isnt able to guess the column name. Since you're setting a variable, @SQL, you're setting a single string and therefore need one row returned. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. 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Starting from a simple query, and getting increasingly more complex, lets look at how this actually works. Connect and share knowledge within a single location that is structured and easy to search. Learn how your comment data is processed. linux , (225, N'ICS225', N'Web Programming') They identify the records present in a table uniquely. FROM #Students s FROM #Students s; The last piece is a bit of data clean up, using a STUFF or SUBSTRING we can remove the extra comma and white space from the comma separated list. INSERT INTO #Students (StudentID, FirstName, LastName) Lets start off by creating a basic table called Person with two columns and three rows of data: This is just a run of the mill SQL query returning 3 rows of data: Here, the output of the Query is formatted into XML with each row represented as a Root node named Person and each column as a child element: The name of each child node under person is determined by the final column name (this is important later). Then it looks at the first character position of the query result and replaces the two characters from that point with a zero length field (). Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company, same here parsing the xml is too costly. One nice little trick with the XML commands that Im grateful for is used to provide a comma-separated list of data. database administration I would materialise this into a #temp table first to ensure it is only evaluated once. This is where STUFF comes in. Here we will implement our firsts bit of trickery. INSERT INTO #Courses ( It is a valuable command that can be a great tool to have under your belt. As an example, I would like to produce a csv list of the surnames from the following data: It comprises of two commands. ) So running the following query will give us all of the values in a comma separated list. Here is another possible T-SQL implementation which uses UNPIVOT/PIVOT: It runs in approximately the same time as Kenneth's solution. I am attempting to write a select statement using STUFF and FOR XML PATH to create a comma separated string in one field. For example: Not valid XML in this form (hence the red underline) but you get the idea. What properties should my fictional HEAT rounds have to punch through heavy armor and ERA? For this SQL FOR XML PATH mode example, We are using the New Employees and . StudentID = s. 3. Wed like to concatenate our fields with a comma, so well add a comma to the select. SQL Stuff For XML Path with Multiple Fields Asked 5 years, 7 months ago Modified 5 years, 7 months ago Viewed 1k times 1 I am using SQL Server 2008. , (10002, 240) The SQL Server T-SQL commands used are STUFF and FOR XML . It is an interesting problem in Transact SQL, for which there are a number of solutions and considerable debate. database security , (240, N'ICS240', N'Advanced Programming') In the next step well find out how to get rid of the second one. SELECT c.CourseCode CREATE TABLE #Students ( FOR XML PATH ('Report'), ROOT ('Reports'); This is a pretty standard SELECT * FROM (<my subselect query>) with the FOR XML stuff on the outside. Using Structured Query Language (SQL) can seem complicated at first, but further, it will become easier and much more convenient. LEFT JOIN #Courses c ON c.CourseID = sc.CourseID However, I had a look at the execution plan and it seemed like probably not the best way to do it. The XML version of the script addresses this limitation by using a combination of XML Path, dynamic T-SQL and some built-in T-SQL functions such as STUFF and QUOTENAME. c# But perhaps you don't want to use one for whatever reason You say that the source for this is an expensive query. Maybe using some XML functions, like . I was recently shown a cool way to concatenate an unlimited number of rows into a single cell in SQL, but was left wondering how it worked under the hood. Each nested call is running for every row of the data returned. LEFT JOIN #Courses c ON c.CourseID = sc.CourseID SQL Aggregate Functionsare functions that perform calculations and return a summarized result. Enter your email address to follow this blog and receive notifications of new posts by email. This is very important since the result of the above query is now a string value and since we used the comma we have now comma seperated values which results as a . t-sql queries value ('.','NVARCHAR (MAX)'),1,2,'') AS [group] FROM [temptable] as a GROUP BY a. Optionally, you can add a string parameter to Path to override the root element name. Asking for help, clarification, or responding to other answers. Ready to optimize your JavaScript with Rust? This will include all data from the student table, all data from the student course weak entity table, and only course code data from the course table. How do I arrange multiple quotations (each with multiple lines) vertically (with a line through the center) so that they're side-by-side? We can state multiple. Note the file name: this is still returning XML (just poorly formatted XML). CREATE TABLE #Courses ( LEFT JOIN #Courses c ON c.CourseID = sc.CourseID. If I could pick and choose which bits I get to play with I suspect I wouldnt be a DBA for long. performance SELECT s.StudentID [user], STUFF ( (SELECT ', ' + [group] [text ()] FROM [temptable] WHERE [user] = a. Execute the following query, and it retrieves the data in a grid format. This trickery actually works out to have an advantage because we need to concatenate our strings with a comma to create a comma separated list of values. As already pointed out by Martin Smith, a CLR aggregate is probably your best bet. SELECT ', ' + c. CourseCode FROM #Students s LEFT JOIN #StudentCourse sc ON sc. StudentID INT PRIMARY KEY NOT NULL From For XML - SQL Server. FOR XML PATH ('test'); will produce XML output thus: Not valid XML in this form (hence the red underline) but you get the idea. This site uses Akismet to reduce spam. FOR XML PATH ('') produces all the MAX (CASE FieldName [.] SELECT ', ' + c.CourseCode Using for xml path('') to convert all rows into a string. FROM #PersonList. AND ssf.serviceid = 1. Examples of frauds discovered because someone tried to mimic a random sequence. of programming knowledge available on the internet FROM #Students s and a humble attempt to contribute to it. GO entity framework , (10002, N'John',N'Johnson') Ive added the ORDER BY just to make the data look more organised and of course the inner XML query can be more involved than this one but it should give an idea of how to use this for this particular purpose: Categories: STUFF, Training, XMLTags: Demo, SQL, STUFF, XML, Your email address will not be published. We need to somehow get rid of the xml markup around our data and weve dropped an entire node. Create a website or blog at WordPress.com. Learn how your comment data is processed. CourseID FOR XML PATH('')) For example, our original string is 7 characters long. Also, if there is a blank column the results will yield extra commas An explicit ORDER BY would be preferable to relying on the order imposed by DISTINCT, even if adding . DROP TABLE IF EXISTS #StudentCourse Thus, we covered the parameters of the STUFF command in T-SQL and understood how this command compares with CONCAT. Thank you. Normally the PATH would have something within it and would therefore produce a very basic XML. The FOR XML clause can be used in top-level queries and in sub queries. (SELECT * FROM (SELECT N',' + N'first' UNION SELECT N',' + N'second') FOR XML PATH('')) The character_expression has to evaluate to obtain a single data value. Well analyze this output to fully understand the STUFF command: Now, the third parameter is increased to values of 4,5,6. , (10004, 140) Database development, Statements. ,FullService,Function 2. , (10001, 225) Detailed article with nice presentation. select test.id, stuff ( (select ', ' + thistable.name from test thistable where test.id = thistable.id and thistable.name <> '' for xml path ('')),1,2,'') as concatenatedsomefield, stuff ( (select ', ' + car from test thistable where test.id = thistable.id and thistable.car <> '' for xml path ('')),1,2,'') as concatenatedsomefield2 from How can I apply the same logic to multiple tables that have the same number of columns and data types? For example, computed columns or nested scalar queries that do not specify column alias will generate columns without any name. Here is the quick script which does the task, ask, I have used temporary tables so you can just take this script and quickly run on your machine and see how it returns results. 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