使用带有字符串数组的IN谓词时，PostgreSQL缺少运算符

鉴于此表结构：

CREATE TABLE tags
(
  id SERIAL NOT NULL PRIMARY KEY,
  tagname TEXT NOT NULL UNIQUE,
  authorid int NOT NULL,
  created timestamp NOT NULL,
  lastmodified timestamp NOT NULL,

  constraint fk_authorid_tags foreign key(authorid) references users(id)
);

为什么以下查询失败并显示错误：

ERROR:  operator does not exist: text = text[]
LINE 2: select * from tags where tagname in ('{"c#","c"}'::text[])

查询：

select * from tags where tagname in ('{"c#","c"}'::text[])