问题
when I run the below query
select concat(column1,column2,column3) as concatcolumn from table
I get an error "ORA-00909:INVALID NUMBER OF ARGUMENTS"
回答1:
Concat only takes two arguments. See: http://docs.oracle.com/cd/B19306_01/server.102/b14200/functions026.htm
Use the concatenation operator:
select column1 || column2 || column3 ...
回答2:
select ([column1]+','+[column2]+','+[column3]) as concatcolumn from table
Try above the query.it may changes on different type of column data type.
来源：https://stackoverflow.com/questions/29917761/how-to-concatenate-more-than-two-columns-in-plsql-developer