Re: [HACKERS] NULL concatenation

[Pavel Stehule <pavel.stehule@xxxxxxxxx>]

Hi

2016-05-12 10:47 GMT+02:00 Sridhar N Bamandlapally <sridhar.bn1@xxxxxxxxx>:

Hi

In migration, am facing issue with NULL concatenation in plpgsql, 

by concatenating NULL between any where/position to Text / Varchar, the total string result is setting value to NULL

In Oracle:

declare

    txt1 VARCHAR2(100) := 'ABCD';

    txt2 VARCHAR2(100) := NULL;

    txt3 VARCHAR2(100) := 'EFGH';

    txt VARCHAR2(100) := NULL;

begin

  txt:= txt1 || txt2 || txt3;

  dbms_output.put_line (txt);

end;

/

abcdefgh   ===>return value

In Postgres

do $$

declare

    txt1 text := 'ABCD';

    txt2 text := NULL;

    txt3 text := 'EFGH';

    txt text := NULL;

begin

    txt:= txt1 || txt2 || txt3;

    raise notice '%', txt;

end$$ language plpgsql;

NOTICE:  <NULL>  ===> return value

SQL-Server also does same like Oracle

Is there any way alternate we have for same behavior in PostgreSQL

use function concat http://www.postgresql.org/docs/9.5/static/functions-string.html

 postgres=# select concat('AHOJ', NULL,'XXX');
 concat 
---------
 AHOJXXX
(1 row)

Regards

Pavel

Please

Thanks

Sridhar

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