Why does accessing a value of the RECORD argument like this works:
CREATE OR REPLACE FUNCTION TT_GetVal1(a RECORD)
RETURNS text AS $$
DECLARE
BEGIN
RETURN a.val1::text;
END;
$$ LANGUAGE plpgsql VOLATILE;
SELECT TT_GetVal1(foo.*)
FROM (SELECT 1 id, 'a' val1) foo;
But not like this:
CREATE OR REPLACE FUNCTION TT_GetVal2(a RECORD)
RETURNS text AS $$
DECLARE
query text;
result text;
BEGIN
query = 'SELECT ($1).val1::text';
EXECUTE query INTO result USING a;
RETURN result;
END;
$$ LANGUAGE plpgsql VOLATILE;
SELECT TT_GetVal2(foo.*)
FROM (SELECT 1 id, 'a' val1) foo;
which returns:
ERROR: could not identify column "val1" in record data type
LINE 1: SELECT ($1).val1::text
How can I dynamically access RECORD values?
The RECORD only lives inside the plpgsql scope. The values are passed to the execute but not the column names.
You can - if the record is from a table - do something like this:
create table table1 (
id integer,
val1 text
);
CREATE OR REPLACE FUNCTION TT_GetVal2(a RECORD)
RETURNS text AS $$
DECLARE
query text;
result text;
BEGIN
query = 'SELECT ($1::text::table1).val1';
EXECUTE query INTO result USING a;
RETURN result;
END;
$$ LANGUAGE plpgsql VOLATILE;
SELECT TT_GetVal2(foo)
FROM (SELECT 1 id, 'a' val1) foo;
Best regards,
Bjarni
Related
I have a simple Postgres function where I want to take table_name as a parameter and pass it into an argument and delete the data from table by condition.
CREATE OR REPLACE FUNCTION cdc.audit_refresh(tablename text)
RETURNS integer AS
$$
BEGIN
delete from tablename where id<4;
RETURN(select 1);
END;
$$ LANGUAGE plpgsql;
select cdc.audit_refresh('cdc.adf_test');
But it throws out an error that tablename
ERROR: relation "tablename" does not exist in the delete statement.(refer snapshot)
What you want to achieve is to execute Dynamic SQL statements. You can do this with EXECUTE. See more here
CREATE OR REPLACE FUNCTION audit_refresh(tablename text)
RETURNS integer AS
$$
DECLARE
stmt TEXT;
BEGIN
stmt = 'delete from '||tablename||' where id<4;';
EXECUTE stmt;
RETURN 1;
END
$$ LANGUAGE plpgsql;
CREATE OR REPLACE FUNCTION "public"."sxfun"("jcbh" text)
RETURNS "pg_catalog"."int4" AS $BODY$
declare leftplayer TEXT;
declare rightplayer TEXT;
declare leftcoin int;
BEGIN
SELECT player1 into leftplayer,player2 into rightplayer FROM table1 WHERE id=$1;
SELECT SUM(playcoin) into leftcoin FROM table2 WHERE playname=leftplayer
COMMIT;
END$BODY$
LANGUAGE plpgsql VOLATILE
COST 100
this code syntax error,let how to solve it,please
You are missing a return statement. In PL/pgSQL, declare starts a block, there is no need to repeat the keyword for every variable. And you can't commit in a function - and you don't need it to begin with.
As documented in the manual you need to use return to return a value from a function.
To store multiple columns into multiple variables, you need to separate them with a comma, not repeat the INTO clause.
Note that sum() returns a bigint, so your variable and return type should also be defined as bigint.
CREATE OR REPLACE FUNCTION public.sxfun(jcbh text)
RETURNS bigint
AS
$BODY$
declare
leftplayer TEXT;
rightplayer TEXT;
leftcoin bigint;
BEGIN
SELECT player1, player2
into leftplayer, rightplayer
FROM table1
WHERE id = jcbh;
SELECT SUM(playcoin)
into leftcoin
FROM table2
WHERE playname = leftplayer;
return leftcoin; --<< return the value
END
$BODY$
LANGUAGE plpgsql;
If id is a number (which the name usually indicates), the parameter jcbh should be declared as integer, not as text.
Note that you can simplify this to a single statement. There is no need for intermediate variables:
CREATE OR REPLACE FUNCTION public.sxfun(jcbh text)
RETURNS bigint
AS
$BODY$
SELECT SUM(playcoin)
FROM table2
WHERE playname IN (select leftplayer
FROM table1
WHERE id = jcbh);
$BODY$
LANGUAGE sql;
I'm a beginner in plpgsql and working on a project which requires me to write a function that returns two variables in the form of 2 columns (res,Result). I've done a quite a bit of searching but didn't find answer for the same. The reference to my code is below
CREATE OR REPLACE FUNCTION propID(character varying)
RETURNS SETOF RECORD AS $val$
DECLARE
t_row record;
res BOOLEAN;
result character varying;
value record;
BEGIN
FOR t_row IN SELECT property_id FROM property_table WHERE ward_id::TEXT = $1 LOOP
RAISE NOTICE 'Analyzing %', t_row;
res := false; -- here i'm going to replace this value with a function whos return type is boolean in future
result := t_row.property_id;
return next result; --here i want to return 2 variables (res,result) in the form of two columns (id,value)
END LOOP;
END;
$val$
language plpgsql;
Any help on the above query would be very much appreciated.
Assuming that property_id and ward_id are integers you can achieve your goal in a simple query like this:
select some_function_returning_boolean(property_id), property_id
from property_table
where ward_id = 1; -- input parameter
If you absolutely need a function, it can be an SQL function like
create or replace function prop_id(integer)
returns table (res boolean, id int) language sql
as $$
select some_function_returning_boolean(property_id), property_id
from property_table
where ward_id = $1
$$;
In a plpgsql function you should use return query:
create or replace function prop_id(integer)
returns table (res boolean, id int) language plpgsql
as $$
begin
return query
select some_function_returning_boolean(property_id), property_id
from property_table
where ward_id = $1;
end
$$;
I'm trying to get a customer id which can be placed in one of ten different tables. I don't want to hard code those table names to find it so I tried postgresql function as follows.
create or replace FUNCTION test() RETURNS SETOF RECORD AS $$
DECLARE
rec record;
BEGIN
select id from schema.table_0201_0228 limit 1 into rec;
return next rec;
select id from schema.table_0301_0331 limit 1 into rec;
return next rec;
END $$ language plpgsql;
select * from test() as (id int)
As I'm not familiar with postgresql function usage, how can I improve the code to replace 'schema.table1' with a variable, loop each table and return the result?
NOTE: table names may change overtime. For example, table_0201_0228 and table_0301_0331 are for February and March respectively.
You need dynamic SQL for that:
create or replace FUNCTION test(p_schema text)
RETURNS table(id int)
AS $$
DECLARE
l_tab record;
l_sql text;
BEGIN
for l_tab in (select schemaname, tablename
from pg_tables
where schemaname = p_schema)
loop
l_sql := format('select id from %I.%I limit 1', l_tab.schemaname, l_tab.tablename);
return query execute l_sql;
end loop;
END $$
language plpgsql;
I made the schema name a parameter, but of course you can hard-code it. As the function is defined as returns table there is no need to specify the column name when using it:
select *
from test('some_schema');
I made a function in pgadmin
create or replace function get_source2(a text)
returns integer as
$$
declare
a text;
geom geometry;
begin
select get_source(geom)
from a;
end;
$$
language plpgsql;
I want input a by table name How can I do? I try to like this
select get_source2('postgis.center')
but I get:
ERROR: relation "a" does not exist LINE 2: from a help me
try this:
create or replace function get_source2(a text)
returns integer as
$$
declare
geom geometry;
begin
execute 'select get_source(geom) from '||quote_ident(a) into geom;
return geom;
end;
$$
language plpgsql;