STUFF function to display multiple columns with comma-separated in SQL Server

问题

I need to display a table column (assume 2 columns) values with comma-separated in the output

col1    Col2    
================
xyz       abc  
pqr       uvw

Output needed:

Col1      Col2
========  =======
xyz,pqr    abc,uvw

I tried below query but not sure how to include col2 to the below query and make it as a single query:

SELECT 
    STUFF((SELECT DISTINCT ',' + CAST(t.Col1 AS VARCHAR(MAX))
           FROM Table_1 t
           FOR XML PATH('')), 1, 1, '')

回答1:

SQL Fiddle

MS SQL Server 2017 Schema Setup:

create table MyTable(ColA varchar(max),ColB varchar(max))
INSERT INTO MyTable(ColA,ColB)VALUES('xyz','abc')
INSERT INTO MyTable(ColA,ColB)VALUES('pqr','uvw')

Query 1:

SELECT STUFF((select  ',' + cast(t.ColA as varchar(max))
from MyTable t
for xml path ('')
), 1, 1, '') AS ColA,
STUFF((select  ',' + cast(t.ColB as varchar(max))
from MyTable t
for xml path ('')
), 1, 1, '') AS ColB

Query 2 :

 SELECT 
       STRING_AGG(colA, ',') AS colA,
       STRING_AGG(colB, ',') AS colB
    FROM MyTable

Results:

|    ColA |    ColB |
|---------|---------|
| xyz,pqr | abc,uvw |

回答2:

This is one possible approach:

Table:

CREATE TABLE Data (
   col1 nvarchar(50),
   col2 nvarchar(50)
)
INSERT INTO Data 
   (col1, col2)
VALUES
   (N'xyz', N'abc'),
   (N'pqr', N'uvw')

Statment:

SELECT 
   Col1 = STUFF((SELECT CONCAT(',', col1) FROM Data FOR XML PATH(''),TYPE).value(N'.','nvarchar(max)'), 1, 1, ''),
   Col2 = STUFF((SELECT CONCAT(',', col2) FROM Data FOR XML PATH(''),TYPE).value(N'.','nvarchar(max)'), 1, 1, '')

Result:

Col1    Col2
xyz,pqr abc,uvw

Notes: If you use SQL Server 2017+, you may use STRING_AGG():

SELECT 
   STRING_AGG(col1, N',') AS col1,
   STRING_AGG(col2, N',') AS col2
FROM Data

来源：https://stackoverflow.com/questions/58656495/stuff-function-to-display-multiple-columns-with-comma-separated-in-sql-server

标签

sql-server

sql-server-2014