Functions in Oracle (wm_concat)

In Oracle, there is a wmsys user. Like sys, system, and other users, this user is created during Oracle installation.

 

The function starting with WM is the function of this user.

 

Wmsys users are mainly responsible for managing the daily work of Oracle (WM: Work manager ),

 

To convert a column into a row.

 

For example

Userid class

001 1

002 1

003 1

004 2

005 2

006 3

 

Use the following SQL

Select

Class, wm_concat (userid)

From

Table

Group

Class

 

Result

1 001,002,003

2 004,005

3 006