入力の最後にPL/pgSQL構文エラーが発生しました

Question

私はPL/pgSQLを使い慣れていません。これは私にとっては試行錯誤のようなものです。空の関数を作成しようとしていますが、呼び出されたときに表が生成されます。ここで私はこれまで持っているものです。

create or replace function counties() 
returns table(code varchar(16), county varchar(50), count int) as $$ 
DECLARE 
    new_version varchar(50) := concat('sometext', max(REGEXP_REPLACE(COALESCE(schema_name, '0'), '[^0-9]*' ,'0')::integer), 'sometext') from information_schema.schemata where schema_name like 'gcversa%'; 
    old_version varchar(50) := concat('sometext', max(REGEXP_REPLACE(COALESCE(schema_name, '0'), '[^0-9]*' ,'0')::integer)-2, 'sometext') from information_schema.schemata where schema_name like 'gcversa%'; 
BEGIN RETURN QUERY 
    with cte_current as (select distinct a.code as code, b.countyname as county from old_version a, public.counties b 
       where st_intersects(a.geom,b.geom) = True group by a.code, b.countyname), 

     cte_new  as (select distinct a.code as code, b.countyname as county from new_version a, public.counties b 
       where st_intersects(a.geom,b.geom) = True group by a.code, b.countyname), 


     cte_union as (select code, county from cte_current 
     union all 
     select code, county from cte_new) 

    select code,county, count(*) as count 
    from cte_union 
    group by code, county 
    Having count (*) <> 2; 
END; 
$$ 
LANGUAGE plpgsql; 

私が宣言している2つの変数が参照し、2つのPostgreSQLのスキーマのを連結した後、私はその後、労働組合それらのために、CTEのにそれらの変数を挿入しようとしていますすべて一緒に。私が正しく実行機能を得たが、私はselect counties()を呼び出すときに、私はこのエラーを取得：

ERROR: relation "old_version" does not exist 
LINE 1: ...tinct a.code as code, b.countyname as county from old_versio... 

だから、それは私が宣言された変数、任意の提案を拾っていませんか？

UPDATE 私は動的SQLとformat（）関数を使用しました。ここでは、最終的な作業モデルがどのように見えるかです：あなたは、ここで動的SQLが必要になります

drop function counties(); 

create or replace function counties() 
returns table(code varchar(16), county varchar(50), count bigint) as $$ 
DECLARE 
    new_version_number varchar(50) := concat('gcversa00', MAX("versionnumber")) from "gcdefault"."versionhistory"; 
    old_version_number varchar(50) := concat('gcversa00', MAX("versionnumber"-2)) from "gcdefault"."versionhistory"; 
BEGIN RETURN QUERY EXECUTE 
format(
    'with cte_current as (select distinct a.code as code, b.countyname as county from %I.servicearea a, public.counties b 
       where st_intersects(a.geom,b.geom) = True group by a.code, b.countyname), 

     cte_new  as (select distinct a.code as code, b.countyname as county from %I.servicearea a, public.counties b 
       where st_intersects(a.geom,b.geom) = True group by a.code, b.countyname), 


     cte_union as (select code, county from cte_current 
     union all 
     select code, county from cte_new) 

    select code,county, count(*) as count 
    from cte_union 
    group by code, county 
    Having count (*) <> 2', new_version_number, old_version_number 
    ); 
END; 
$$ 
LANGUAGE plpgsql; 

Answer 1

例：

t=# create or replace function ds() returns table (i int) as 
$$ 
declare 
tn text := 'pg_database'; 
begin 
return query execute format('select oid::int from %I',tn); 
end; 
$$language plpgsql 
; 
CREATE FUNCTION 
t=# select * from ds(); 
    i 
----------- 
     1 
    12945 
    12950 
    12963038 
111274822 
    32059515 
    26947889 
173381559 
    32061155 
    32061156 
    82287221 
203004236 
214018521 
(13 rows)