PostgreSQL中的AnyArray例子

http://www.joeconway.com/presentations/function_basics.pdf

CREATE FUNCTION myappend(anyarray, anyelement) RETURNS anyarray AS
$$
SELECT $1 || $2;
$$ LANGUAGE SQL;

查询一：

pgsql=# SELECT myappend(ARRAY[42,6], 21);
 myappend  
-----------
 {42,6,21}
(1 row)

pgsql=# 

查询二：

pgsql=# SELECT myappend(ARRAY['abc','def'], 'xyz');
   myappend    
---------------
 {abc,def,xyz}
(1 row)

pgsql=# 

查询三：

pgsql=# SELECT myappend(ARRAY['abc','def','kkk'], 'xyz');
     myappend      
-------------------
 {abc,def,kkk,xyz}
(1 row)

pgsql=#