Re: PG function with pseudotype "anyelement" for IN, OUT parameter shows wrong behaviour.

2020-05-29 Thread Prabhat Sahu
On Fri, May 29, 2020 at 8:30 PM Pavel Stehule 
wrote:

>
>
> pá 29. 5. 2020 v 16:45 odesílatel Prabhat Sahu <
> prabhat.s...@enterprisedb.com> napsal:
>
>> Hi All,
>>
>> Please check the below scenario, with pseudotype "anyelement" for IN, OUT
>> parameter and the RETURN record in a function.
>>
>> postgres=# create table tab1(c1 int, c2 int, c3 timestamp) ;
>> CREATE TABLE
>> postgres=# CREATE OR REPLACE FUNCTION func_any(IN anyelement, IN
>> anyelement, OUT v1 anyelement, OUT v2 anyelement)
>> RETURNS record
>> AS
>> $$
>> BEGIN
>>   SELECT $1 + 1, $2 + 1 into v1, v2;
>>   insert into tab1 values(v1, v2, now());
>> END;
>> $$
>> language 'plpgsql';
>> CREATE FUNCTION
>> postgres=# SELECT (func_any(1, 2)).*;
>>  v1 | v2
>> +
>>   2 |  3
>> (1 row)
>>
>> postgres=# select * from tab1;
>>  c1 | c2 | c3
>> ++
>>   2 |  3 | 2020-05-30 19:26:32.036924
>>   2 |  3 | 2020-05-30 19:26:32.036924
>> (2 rows)
>>
>> I hope, the table "tab1" should have only a single record, but we are
>> able to see 2 records in tab1.
>>
>
> it is correct, because you use composite unpacking syntax
>
> SELECT (func_any(1, 2)).*;
>
> means
>
> SELECT (func_any(1, 2)).c1, (func_any(1, 2)).c2;
>
> If you don't want double execution, you should to run your function in
> FROM clause
>
> postgres=# SELECT * FROM func_any(1, 2);
> ┌┬┐
> │ v1 │ v2 │
> ╞╪╡
> │  2 │  3 │
> └┴┘
> (1 row)
>

Thanks Pavel, for the help, I have verified the same, Now I am getting a
single record in tab1.
postgres=# SELECT func_any(1, 2);
 func_any
--
 (2,3)
(1 row)

postgres=# select * from tab1;
 c1 | c2 | c3
++
  2 |  3 | 2020-05-30 20:17:59.989087
(1 row)
Thanks,
Prabhat Sahu


Re: PG function with pseudotype "anyelement" for IN, OUT parameter shows wrong behaviour.

2020-05-29 Thread Pavel Stehule
pá 29. 5. 2020 v 16:45 odesílatel Prabhat Sahu <
prabhat.s...@enterprisedb.com> napsal:

> Hi All,
>
> Please check the below scenario, with pseudotype "anyelement" for IN, OUT
> parameter and the RETURN record in a function.
>
> postgres=# create table tab1(c1 int, c2 int, c3 timestamp) ;
> CREATE TABLE
> postgres=# CREATE OR REPLACE FUNCTION func_any(IN anyelement, IN
> anyelement, OUT v1 anyelement, OUT v2 anyelement)
> RETURNS record
> AS
> $$
> BEGIN
>   SELECT $1 + 1, $2 + 1 into v1, v2;
>   insert into tab1 values(v1, v2, now());
> END;
> $$
> language 'plpgsql';
> CREATE FUNCTION
> postgres=# SELECT (func_any(1, 2)).*;
>  v1 | v2
> +
>   2 |  3
> (1 row)
>
> postgres=# select * from tab1;
>  c1 | c2 | c3
> ++
>   2 |  3 | 2020-05-30 19:26:32.036924
>   2 |  3 | 2020-05-30 19:26:32.036924
> (2 rows)
>
> I hope, the table "tab1" should have only a single record, but we are able
> to see 2 records in tab1.
>

it is correct, because you use composite unpacking syntax

SELECT (func_any(1, 2)).*;

means

SELECT (func_any(1, 2)).c1, (func_any(1, 2)).c2;

If you don't want double execution, you should to run your function in FROM
clause

postgres=# SELECT * FROM func_any(1, 2);
┌┬┐
│ v1 │ v2 │
╞╪╡
│  2 │  3 │
└┴┘
(1 row)

Regards

Pavel



> --
>
> With Regards,
> Prabhat Kumar Sahu
> EnterpriseDB: http://www.enterprisedb.com
>


PG function with pseudotype "anyelement" for IN, OUT parameter shows wrong behaviour.

2020-05-29 Thread Prabhat Sahu
Hi All,

Please check the below scenario, with pseudotype "anyelement" for IN, OUT
parameter and the RETURN record in a function.

postgres=# create table tab1(c1 int, c2 int, c3 timestamp) ;
CREATE TABLE
postgres=# CREATE OR REPLACE FUNCTION func_any(IN anyelement, IN
anyelement, OUT v1 anyelement, OUT v2 anyelement)
RETURNS record
AS
$$
BEGIN
  SELECT $1 + 1, $2 + 1 into v1, v2;
  insert into tab1 values(v1, v2, now());
END;
$$
language 'plpgsql';
CREATE FUNCTION
postgres=# SELECT (func_any(1, 2)).*;
 v1 | v2
+
  2 |  3
(1 row)

postgres=# select * from tab1;
 c1 | c2 | c3
++
  2 |  3 | 2020-05-30 19:26:32.036924
  2 |  3 | 2020-05-30 19:26:32.036924
(2 rows)

I hope, the table "tab1" should have only a single record, but we are able
to see 2 records in tab1.

-- 

With Regards,
Prabhat Kumar Sahu
EnterpriseDB: http://www.enterprisedb.com