在PostgreSQL中的concat

Question

我使用postgresql创建了一个函数。但是，当我尝试执行此函数时，它会返回错误。错误"ERROR: syntax error at or near "||"

CREATE OR REPLACE FUNCTION search_address_book(address_ids character)
  RETURNS void AS
$BODY$ 
SET sqlStatement = 'select * from addressbook';
SET address_ids = 'Post' || 'greSQL';
$BODY$
LANGUAGE 'sql' STABLE
COST 100;

我的服务器版本是8.3.14。错了吗 我如何在PostgreSQL中连接两个字符串？

Answer 1

要使用变量，您需要一个plpgsql函数：

CREATE OR REPLACE FUNCTION search_address_book(address_ids character)
  RETURNS void AS
$BODY$
declare
   sqlStatement text;
   address_ids text;
begin
   sqlStatement := 'select * from addressbook';
   address_ids := 'Post' || 'greSQL';
end
$BODY$
LANGUAGE plpgsql STABLE;