oracle 拼接varchar类型字段，listagg 合并行数据，listagg 去重_oracle listagg 值重复合并

SELECT 
    teacher.id,
	regexp_replace(listagg(Concat(teacher.name,teacher.remark), ',' ) within GROUP ( ORDER BY student.name), '([^,]+)(,\1)+', '\1') AS tercher_info 
FROM
	student student
	LEFT JOIN teacher teacher ON student.teacher_id = student.id 
group by student.teacher_id;
 
#拼接varchar类型字段：Concat(teacher.name,teacher.remark)
#根据分组，把数据拼接在一起：listagg(Concat(teacher.name,teacher.remark), ',' ) within GROUP ( ORDER BY student.name)
#listagg去重：regexp_replace(listagg(Concat(teacher.name,teacher.remark), ',' ) within GROUP ( ORDER BY student.name), '([^,]+)(,\1)+', '\1')