Related
So I'm trying to rewrite a MySQL query to MSSQL, but it's not as easy as I thought, since the functions from MySQL are not used in MSSQL(2014).
My MySQL query looks like this:
SELECT
(SELECT
REPLACE(GROUP_CONCAT(DISTINCT CONCAT(versions.Name, ': ', versions.Version)),
',',
', </br>') AS VersionString
FROM
target
LEFT JOIN
versions ON versions.targetid = target.id
WHERE
target.TestJobId = testruns.TestJobId
AND versions.Name = 'SW') AS NameVersion
FROM
testruns
I've tried to rewrite it, but I can't seem to make it work.
SELECT
(SELECT stuff(
(SELECT DISTINCT ', <br>' + cast([testreportingdebug].versions.Name + ': ' + [testreportingdebug].versions.Version AS VARCHAR(max))
FROM [SwMetrics].[testreportingdebug].[target]
FOR XML path('')
), 1, 1, '') AS VersionString
FROM
[testreportingdebug].[target]
LEFT JOIN
[testreportingdebug].[versions] ON [testreportingdebug].[versions].[targetid] = [testreportingdebug].[target].[id]
WHERE
[testreportingdebug].[target].[TestJobId] = [testreportingdebug].[testruns].[TestJobId]
AND [testreportingdebug].[versions].[Name] = 'SW') AS NameVersion
FROM
[testreportingdebug].[testruns];
The error I get is:
Msg 512, Level 16, State 1, Line 1
Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.
I'm a bit stuck what/how to rewrite this query. How can I rewrite it to work in SQL Server?
In SQL server STRING_AGG() replaces GROUP_CONCAT() and we can specify the seperator as </br>.
SELECT
STRING_AGG(
DISTINCT CONCAT(
versions.Name,
': ',
versions.Version,
'</br') AS VersionString
FROM target
LEFT JOIN versions
ON versions.targetid = target.id
AND target.TestJobId = testruns.TestJobId
WHERE versions.Name = 'SW';
Say I have two JSON strings as follows:
[{"RowId":102787,"UserId":1,"Activity":"This is another test","Timestamp":"2017-11-25T14:37:30.3700000"}]
[{"RowId":102787,"UserId":2,"Activity":"Testing the Update function","Timestamp":"2017-11-25T14:37:30.3700000"}]
Both have the same properties but two of the properties in the second string have different values than the first (UserId and Activity). Is it possible, in Azure SQL Database T-SQL, to generate a third JSON string that contains the values in the second string that are different from the first? In other words, I'd like a string returned that looks like this:
[{"UserId":2,"Activity":"Testing the Update function"}]
Also, the solution should assume that the properties in the JSON strings are not known. I need this to be a generic solution for any two JSON strings.
Have not tried this on Azure, but it seems to work on SQL Server 2017
There is probably a more elegant way to get to the final JSON string other than through string manipulation, perhaps we can update the answer as better ways are found.
-- Expected : [{"UserId":2,"Activity":"Testing the Update function"}]
DECLARE #jsonA NVARCHAR(MAX) = '[{"RowId":102787,"UserId":1,"Activity":"This is another test","Timestamp":"2017-11-25T14:37:30.3700000"}]'
,#jsonB NVARCHAR(MAX) = '[{"RowId":102787,"UserId":2,"Activity":"Testing the Update function","Timestamp":"2017-11-25T14:37:30.3700000"}]'
,#result NVARCHAR(MAX) = ''
SELECT #jsonA = REPLACE(REPLACE(#jsonA, ']', ''), '[', '')
,#jsonB = REPLACE(REPLACE(#jsonB, ']', ''), '[', '')
;WITH DSA AS
(
SELECT *
FROM OPENJSON(#jsonA)
)
,DSB AS
(
SELECT *
FROM OPENJSON(#jsonB)
)
SELECT #result += CONCAT (
'"', B.[key], '":'
,IIF(B.[type] = 2, B.[value], CONCAT('"', B.[value], '"')) -- havent checked types other than 1 and 2; think there's a bool type?
,','
)
FROM DSA A
JOIN DSB B ON A.[key] = B.[key]
WHERE A.[value] != B.[value]
SELECT CONCAT('[{', LEFT(#result, LEN(#result) - 1), '}]')
I'm trying to migrate a MySQL-based app over to Microsoft SQL Server 2005 (not by choice, but that's life).
In the original app, we used almost entirely ANSI-SQL compliant statements, with one significant exception -- we used MySQL's group_concat function fairly frequently.
group_concat, by the way, does this: given a table of, say, employee names and projects...
SELECT empName, projID FROM project_members;
returns:
ANDY | A100
ANDY | B391
ANDY | X010
TOM | A100
TOM | A510
... and here's what you get with group_concat:
SELECT
empName, group_concat(projID SEPARATOR ' / ')
FROM
project_members
GROUP BY
empName;
returns:
ANDY | A100 / B391 / X010
TOM | A100 / A510
So what I'd like to know is: Is it possible to write, say, a user-defined function in SQL Server which emulates the functionality of group_concat?
I have almost no experience using UDFs, stored procedures, or anything like that, just straight-up SQL, so please err on the side of too much explanation :)
No REAL easy way to do this. Lots of ideas out there, though.
Best one I've found:
SELECT table_name, LEFT(column_names , LEN(column_names )-1) AS column_names
FROM information_schema.columns AS extern
CROSS APPLY
(
SELECT column_name + ','
FROM information_schema.columns AS intern
WHERE extern.table_name = intern.table_name
FOR XML PATH('')
) pre_trimmed (column_names)
GROUP BY table_name, column_names;
Or a version that works correctly if the data might contain characters such as <
WITH extern
AS (SELECT DISTINCT table_name
FROM INFORMATION_SCHEMA.COLUMNS)
SELECT table_name,
LEFT(y.column_names, LEN(y.column_names) - 1) AS column_names
FROM extern
CROSS APPLY (SELECT column_name + ','
FROM INFORMATION_SCHEMA.COLUMNS AS intern
WHERE extern.table_name = intern.table_name
FOR XML PATH(''), TYPE) x (column_names)
CROSS APPLY (SELECT x.column_names.value('.', 'NVARCHAR(MAX)')) y(column_names)
I may be a bit late to the party but this method works for me and is easier than the COALESCE method.
SELECT STUFF(
(SELECT ',' + Column_Name
FROM Table_Name
FOR XML PATH (''))
, 1, 1, '')
SQL Server 2017 does introduce a new aggregate function
STRING_AGG ( expression, separator).
Concatenates the values of string expressions and places separator
values between them. The separator is not added at the end of string.
The concatenated elements can be ordered by appending WITHIN GROUP (ORDER BY some_expression)
For versions 2005-2016 I typically use the XML method in the accepted answer.
This can fail in some circumstances however. e.g. if the data to be concatenated contains CHAR(29) you see
FOR XML could not serialize the data ... because it
contains a character (0x001D) which is not allowed in XML.
A more robust method that can deal with all characters would be to use a CLR aggregate. However applying an ordering to the concatenated elements is more difficult with this approach.
The method of assigning to a variable is not guaranteed and should be avoided in production code.
Possibly too late to be of benefit now, but is this not the easiest way to do things?
SELECT empName, projIDs = replace
((SELECT Surname AS [data()]
FROM project_members
WHERE empName = a.empName
ORDER BY empName FOR xml path('')), ' ', REQUIRED SEPERATOR)
FROM project_members a
WHERE empName IS NOT NULL
GROUP BY empName
Have a look at the GROUP_CONCAT project on Github, I think I does exactly what you are searching for:
This project contains a set of SQLCLR User-defined Aggregate functions (SQLCLR UDAs) that collectively offer similar functionality to the MySQL GROUP_CONCAT function. There are multiple functions to ensure the best performance based on the functionality required...
To concatenate all the project manager names from projects that have multiple project managers write:
SELECT a.project_id,a.project_name,Stuff((SELECT N'/ ' + first_name + ', '+last_name FROM projects_v
where a.project_id=project_id
FOR
XML PATH(''),TYPE).value('text()[1]','nvarchar(max)'),1,2,N''
) mgr_names
from projects_v a
group by a.project_id,a.project_name
With the below code you have to set PermissionLevel=External on your project properties before you deploy, and change the database to trust external code (be sure to read elsewhere about security risks and alternatives [like certificates]) by running ALTER DATABASE database_name SET TRUSTWORTHY ON.
using System;
using System.Collections.Generic;
using System.Data.SqlTypes;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using Microsoft.SqlServer.Server;
[Serializable]
[SqlUserDefinedAggregate(Format.UserDefined,
MaxByteSize=8000,
IsInvariantToDuplicates=true,
IsInvariantToNulls=true,
IsInvariantToOrder=true,
IsNullIfEmpty=true)]
public struct CommaDelimit : IBinarySerialize
{
[Serializable]
private class StringList : List<string>
{ }
private StringList List;
public void Init()
{
this.List = new StringList();
}
public void Accumulate(SqlString value)
{
if (!value.IsNull)
this.Add(value.Value);
}
private void Add(string value)
{
if (!this.List.Contains(value))
this.List.Add(value);
}
public void Merge(CommaDelimit group)
{
foreach (string s in group.List)
{
this.Add(s);
}
}
void IBinarySerialize.Read(BinaryReader reader)
{
IFormatter formatter = new BinaryFormatter();
this.List = (StringList)formatter.Deserialize(reader.BaseStream);
}
public SqlString Terminate()
{
if (this.List.Count == 0)
return SqlString.Null;
const string Separator = ", ";
this.List.Sort();
return new SqlString(String.Join(Separator, this.List.ToArray()));
}
void IBinarySerialize.Write(BinaryWriter writer)
{
IFormatter formatter = new BinaryFormatter();
formatter.Serialize(writer.BaseStream, this.List);
}
}
I've tested this using a query that looks like:
SELECT
dbo.CommaDelimit(X.value) [delimited]
FROM
(
SELECT 'D' [value]
UNION ALL SELECT 'B' [value]
UNION ALL SELECT 'B' [value] -- intentional duplicate
UNION ALL SELECT 'A' [value]
UNION ALL SELECT 'C' [value]
) X
And yields: A, B, C, D
Tried these but for my purposes in MS SQL Server 2005 the following was most useful, which I found at xaprb
declare #result varchar(8000);
set #result = '';
select #result = #result + name + ' '
from master.dbo.systypes;
select rtrim(#result);
#Mark as you mentioned it was the space character that caused issues for me.
About J Hardiman's answer, how about:
SELECT empName, projIDs=
REPLACE(
REPLACE(
(SELECT REPLACE(projID, ' ', '-somebody-puts-microsoft-out-of-his-misery-please-') AS [data()] FROM project_members WHERE empName=a.empName FOR XML PATH('')),
' ',
' / '),
'-somebody-puts-microsoft-out-of-his-misery-please-',
' ')
FROM project_members a WHERE empName IS NOT NULL GROUP BY empName
By the way, is the use of "Surname" a typo or am i not understanding a concept here?
Anyway, thanks a lot guys cuz it saved me quite some time :)
2021
#AbdusSalamAzad's answer is the correct one.
SELECT STRING_AGG(my_col, ',') AS my_result FROM my_tbl;
If the result is too big, you may get error "STRING_AGG aggregation result exceeded the limit of 8000 bytes. Use LOB types to avoid result truncation." , which can be fixed by changing the query to this:
SELECT STRING_AGG(convert(varchar(max), my_col), ',') AS my_result FROM my_tbl;
For my fellow Googlers out there, here's a very simple plug-and-play solution that worked for me after struggling with the more complex solutions for a while:
SELECT
distinct empName,
NewColumnName=STUFF((SELECT ','+ CONVERT(VARCHAR(10), projID )
FROM returns
WHERE empName=t.empName FOR XML PATH('')) , 1 , 1 , '' )
FROM
returns t
Notice that I had to convert the ID into a VARCHAR in order to concatenate it as a string. If you don't have to do that, here's an even simpler version:
SELECT
distinct empName,
NewColumnName=STUFF((SELECT ','+ projID
FROM returns
WHERE empName=t.empName FOR XML PATH('')) , 1 , 1 , '' )
FROM
returns t
All credit for this goes to here:
https://social.msdn.microsoft.com/Forums/sqlserver/en-US/9508abc2-46e7-4186-b57f-7f368374e084/replicating-groupconcat-function-of-mysql-in-sql-server?forum=transactsql
For SQL Server 2017+, use STRING_AGG() function
SELECT STRING_AGG(Genre, ',') AS Result
FROM Genres;
Sample result:
Result
Rock,Jazz,Country,Pop,Blues,Hip Hop,Rap,Punk
I am currently building a number of logging and analysis tools to keep tabs on our SQL environment. We are currently using SQL Server 2014.
What I want to do is keep check of all the parameters that are passed to our reports during the day. All of the reports are currently using stored procedures so in my table or a select statement based on a table is output the stored procedure with the parameters for every time the report was run.
At the end of the day I would then like to be able to take the outputted statement and run it in SSMS without having to use the report. I have been looking at the ExceutionLogStorage table and the ExecutionLog view's and though it has most of the information that I need, the parameters are not in an easily usable state.
Has anyone done something similar to what I have described?
You need to add logging part in your original SP, for example:
Alter procedure a
(#parameter)
As
Begin
..
..
Insert into loggingTable(col)
Values(#parameter)
..
..
End
Then query directly against that loggingTable for getting the history of used parameters
A Google search around this topic quickly brought up the following blog post already identified by the OP as useful and shown below (this query itself is actually an expansion of work linked to by LONG's answer below)
SELECT TOP 1 ParValue
FROM (
SELECT els.TimeEnd
, IIF(CHARINDEX('&' + 'ParameterName' + '=', ParsString) = 0, 'ParameterName',
SUBSTRING(ParsString
, StartIndex
, CHARINDEX('&', ParsString, StartIndex) - StartIndex)) AS ParValue
FROM (SELECT ReportID, TimeEnd
, '&' + CONVERT(VARCHAR(MAX), Parameters) + '&' AS ParsString
, CHARINDEX('&' + 'ParameterName' + '=', '&' + CONVERT(VARCHAR(MAX), Parameters) + '&')
+ LEN('&' + 'ParameterName' + '=') AS StartIndex
FROM ExecutionLogStorage
WHERE UserName='UserName' -- e.g. DOMAIN\Joe_Smith
) AS els
INNER JOIN [Catalog] AS c ON c.ItemID = els.ReportID
WHERE c.Name = 'ReportName'
UNION ALL
SELECT CAST('2000-01-01' AS DateTime), 'ParameterName'
) i
ORDER BY TimeEnd DESC;
Both these approaches though really only give us a starting point since they (variously) rely upon us knowing in advance the report name and parameter names. Whilst we can quickly make a couple of changes to Ken Bowman's work to get it to run against all executions of all reports, we still have the problem that the query hardcodes the parameter name.
The parameters required to execute a report are stored on the Catalog table in the Parameter column. Although the column has a datatype ntext, it is actually storing an XML string. Meaning we can use an XPath query to get at the parameter names
with
CatalogData as (
select ItemID, [Path], [Name], cast(Parameter as xml) 'ParameterXml'
from Catalog
where [Type] = 2),
ReportParameters as (
select ItemID, [Path], [Name], ParameterXml, p.value('Name[1]', 'nvarchar(256)') 'ParameterName'
from CatalogData
cross apply ParameterXml.nodes('/Parameters/Parameter') as Parameters(p))
select *
from ReportParameters;
Executing this query will list all reports on the server and their parameters. Now we just need to combine this with Ken Bowman's query. I've gone with a CTE approach
with
CatalogData as (
select ItemID, [Path], [Name], cast(Parameter as xml) 'ParameterXml'
from Catalog
where [Type] = 2),
ReportParameters as (
select ItemID, [Path], [Name], p.value('Name[1]', 'nvarchar(256)') 'ParameterName'
from CatalogData
cross apply ParameterXml.nodes('/Parameters/Parameter') as Parameters(p))
select
els.TimeEnd
, c.[Name]
, rp.ParameterName
, iif(
charindex(
'&' + rp.ParameterName + '=', ParametersString) = 0
, rp.ParameterName, substring(ParametersString
, StartIndex, charindex('&', ParametersString, StartIndex) - StartIndex
)) 'ParameterValue'
from (
select
ReportID
, TimeEnd
, rp.ParameterName
, '&' + convert(varchar(max), Parameters) + '&' 'ParametersString'
, charindex(
'&' + rp.ParameterName + '=',
'&' + convert(varchar(max), Parameters) + '&'
) + len('&' + rp.ParameterName + '=') 'StartIndex'
from
ExecutionLogStorage
inner join ReportParameters rp on rp.ItemID = ReportID) AS els
inner join [Catalog] c on c.ItemID = els.ReportID
inner join ReportParameters rp on rp.ItemID = c.ItemID and rp.ParameterName = els.ParameterName;
Note that the parameter values are passed to the report as part of a URL, so you'll still need get rid the literal space encoding and so on. Also, this doesn't (yet...) work for multi-value parameters.
I'm trying to migrate a MySQL-based app over to Microsoft SQL Server 2005 (not by choice, but that's life).
In the original app, we used almost entirely ANSI-SQL compliant statements, with one significant exception -- we used MySQL's group_concat function fairly frequently.
group_concat, by the way, does this: given a table of, say, employee names and projects...
SELECT empName, projID FROM project_members;
returns:
ANDY | A100
ANDY | B391
ANDY | X010
TOM | A100
TOM | A510
... and here's what you get with group_concat:
SELECT
empName, group_concat(projID SEPARATOR ' / ')
FROM
project_members
GROUP BY
empName;
returns:
ANDY | A100 / B391 / X010
TOM | A100 / A510
So what I'd like to know is: Is it possible to write, say, a user-defined function in SQL Server which emulates the functionality of group_concat?
I have almost no experience using UDFs, stored procedures, or anything like that, just straight-up SQL, so please err on the side of too much explanation :)
No REAL easy way to do this. Lots of ideas out there, though.
Best one I've found:
SELECT table_name, LEFT(column_names , LEN(column_names )-1) AS column_names
FROM information_schema.columns AS extern
CROSS APPLY
(
SELECT column_name + ','
FROM information_schema.columns AS intern
WHERE extern.table_name = intern.table_name
FOR XML PATH('')
) pre_trimmed (column_names)
GROUP BY table_name, column_names;
Or a version that works correctly if the data might contain characters such as <
WITH extern
AS (SELECT DISTINCT table_name
FROM INFORMATION_SCHEMA.COLUMNS)
SELECT table_name,
LEFT(y.column_names, LEN(y.column_names) - 1) AS column_names
FROM extern
CROSS APPLY (SELECT column_name + ','
FROM INFORMATION_SCHEMA.COLUMNS AS intern
WHERE extern.table_name = intern.table_name
FOR XML PATH(''), TYPE) x (column_names)
CROSS APPLY (SELECT x.column_names.value('.', 'NVARCHAR(MAX)')) y(column_names)
I may be a bit late to the party but this method works for me and is easier than the COALESCE method.
SELECT STUFF(
(SELECT ',' + Column_Name
FROM Table_Name
FOR XML PATH (''))
, 1, 1, '')
SQL Server 2017 does introduce a new aggregate function
STRING_AGG ( expression, separator).
Concatenates the values of string expressions and places separator
values between them. The separator is not added at the end of string.
The concatenated elements can be ordered by appending WITHIN GROUP (ORDER BY some_expression)
For versions 2005-2016 I typically use the XML method in the accepted answer.
This can fail in some circumstances however. e.g. if the data to be concatenated contains CHAR(29) you see
FOR XML could not serialize the data ... because it
contains a character (0x001D) which is not allowed in XML.
A more robust method that can deal with all characters would be to use a CLR aggregate. However applying an ordering to the concatenated elements is more difficult with this approach.
The method of assigning to a variable is not guaranteed and should be avoided in production code.
Possibly too late to be of benefit now, but is this not the easiest way to do things?
SELECT empName, projIDs = replace
((SELECT Surname AS [data()]
FROM project_members
WHERE empName = a.empName
ORDER BY empName FOR xml path('')), ' ', REQUIRED SEPERATOR)
FROM project_members a
WHERE empName IS NOT NULL
GROUP BY empName
Have a look at the GROUP_CONCAT project on Github, I think I does exactly what you are searching for:
This project contains a set of SQLCLR User-defined Aggregate functions (SQLCLR UDAs) that collectively offer similar functionality to the MySQL GROUP_CONCAT function. There are multiple functions to ensure the best performance based on the functionality required...
To concatenate all the project manager names from projects that have multiple project managers write:
SELECT a.project_id,a.project_name,Stuff((SELECT N'/ ' + first_name + ', '+last_name FROM projects_v
where a.project_id=project_id
FOR
XML PATH(''),TYPE).value('text()[1]','nvarchar(max)'),1,2,N''
) mgr_names
from projects_v a
group by a.project_id,a.project_name
With the below code you have to set PermissionLevel=External on your project properties before you deploy, and change the database to trust external code (be sure to read elsewhere about security risks and alternatives [like certificates]) by running ALTER DATABASE database_name SET TRUSTWORTHY ON.
using System;
using System.Collections.Generic;
using System.Data.SqlTypes;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using Microsoft.SqlServer.Server;
[Serializable]
[SqlUserDefinedAggregate(Format.UserDefined,
MaxByteSize=8000,
IsInvariantToDuplicates=true,
IsInvariantToNulls=true,
IsInvariantToOrder=true,
IsNullIfEmpty=true)]
public struct CommaDelimit : IBinarySerialize
{
[Serializable]
private class StringList : List<string>
{ }
private StringList List;
public void Init()
{
this.List = new StringList();
}
public void Accumulate(SqlString value)
{
if (!value.IsNull)
this.Add(value.Value);
}
private void Add(string value)
{
if (!this.List.Contains(value))
this.List.Add(value);
}
public void Merge(CommaDelimit group)
{
foreach (string s in group.List)
{
this.Add(s);
}
}
void IBinarySerialize.Read(BinaryReader reader)
{
IFormatter formatter = new BinaryFormatter();
this.List = (StringList)formatter.Deserialize(reader.BaseStream);
}
public SqlString Terminate()
{
if (this.List.Count == 0)
return SqlString.Null;
const string Separator = ", ";
this.List.Sort();
return new SqlString(String.Join(Separator, this.List.ToArray()));
}
void IBinarySerialize.Write(BinaryWriter writer)
{
IFormatter formatter = new BinaryFormatter();
formatter.Serialize(writer.BaseStream, this.List);
}
}
I've tested this using a query that looks like:
SELECT
dbo.CommaDelimit(X.value) [delimited]
FROM
(
SELECT 'D' [value]
UNION ALL SELECT 'B' [value]
UNION ALL SELECT 'B' [value] -- intentional duplicate
UNION ALL SELECT 'A' [value]
UNION ALL SELECT 'C' [value]
) X
And yields: A, B, C, D
Tried these but for my purposes in MS SQL Server 2005 the following was most useful, which I found at xaprb
declare #result varchar(8000);
set #result = '';
select #result = #result + name + ' '
from master.dbo.systypes;
select rtrim(#result);
#Mark as you mentioned it was the space character that caused issues for me.
About J Hardiman's answer, how about:
SELECT empName, projIDs=
REPLACE(
REPLACE(
(SELECT REPLACE(projID, ' ', '-somebody-puts-microsoft-out-of-his-misery-please-') AS [data()] FROM project_members WHERE empName=a.empName FOR XML PATH('')),
' ',
' / '),
'-somebody-puts-microsoft-out-of-his-misery-please-',
' ')
FROM project_members a WHERE empName IS NOT NULL GROUP BY empName
By the way, is the use of "Surname" a typo or am i not understanding a concept here?
Anyway, thanks a lot guys cuz it saved me quite some time :)
2021
#AbdusSalamAzad's answer is the correct one.
SELECT STRING_AGG(my_col, ',') AS my_result FROM my_tbl;
If the result is too big, you may get error "STRING_AGG aggregation result exceeded the limit of 8000 bytes. Use LOB types to avoid result truncation." , which can be fixed by changing the query to this:
SELECT STRING_AGG(convert(varchar(max), my_col), ',') AS my_result FROM my_tbl;
For my fellow Googlers out there, here's a very simple plug-and-play solution that worked for me after struggling with the more complex solutions for a while:
SELECT
distinct empName,
NewColumnName=STUFF((SELECT ','+ CONVERT(VARCHAR(10), projID )
FROM returns
WHERE empName=t.empName FOR XML PATH('')) , 1 , 1 , '' )
FROM
returns t
Notice that I had to convert the ID into a VARCHAR in order to concatenate it as a string. If you don't have to do that, here's an even simpler version:
SELECT
distinct empName,
NewColumnName=STUFF((SELECT ','+ projID
FROM returns
WHERE empName=t.empName FOR XML PATH('')) , 1 , 1 , '' )
FROM
returns t
All credit for this goes to here:
https://social.msdn.microsoft.com/Forums/sqlserver/en-US/9508abc2-46e7-4186-b57f-7f368374e084/replicating-groupconcat-function-of-mysql-in-sql-server?forum=transactsql
For SQL Server 2017+, use STRING_AGG() function
SELECT STRING_AGG(Genre, ',') AS Result
FROM Genres;
Sample result:
Result
Rock,Jazz,Country,Pop,Blues,Hip Hop,Rap,Punk