Function in Pgadmin Throws operator does not exist error - postgresql

I modified the function to trim all values in multiple tables based on Trim Spaces inside whole Database as below:
create function trim_all_text()
RETURNS void AS $$
DECLARE QL VARCHAR;
BEGIN
QL ='';
-- stored procedure body
PERFORM QL = QL || 'UPDATE T SET T.'||IC.COLUMN_NAME ||
' = LTRIM(RTRIM(' || IC.COLUMN_NAME||'))
FROM '|| IT.TABLE_SCHEMA || '.[' || IT.TABLE_NAME ||
'] AS T ;' || CHR(13)
FROM INFORMATION_SCHEMA.TABLES IT
JOIN INFORMATION_SCHEMA.COLUMNS IC ON IT.TABLE_NAME = IC.TABLE_NAME
AND IT.TABLE_SCHEMA ='public' and IT.TABLE_SCHEMA = IC.TABLE_SCHEMA AND IT.TABLE_TYPE = 'BASE TABLE'
and IC.DATA_TYPE in( 'varchar','char','nvarchar','nchar', 'text');
END;
$$ LANGUAGE plpgsql;
When I run the function in pgadmin4, I receive the error below:
ERROR: operator does not exist: unknown + information_schema.sql_identifier
LINE 1: SELECT QL += 'UPDATE ' + IT.TABLE_SCHEMA + '.'
^
How can I combine strings in a query?

Related

Something wrong with execute in PostgreSQL

I make function that will change type of columns of any table. And for example I create a table test:
create table test(id text, name text, born text);
insert into test values ('1', 'Ivanov', '10-10-2012'), ('2', 'Petrov', '01-01-1999'),
('3', 'Sidorov', '03-12-1975');
And then make table with column name and new data type:
create table col_types(column_name text, data_type text);
insert into col_types values ('id', 'integer'), ('name', 'text'),
('born', 'date');
This my function:
create or replace function change_columns(my_table text, columns_types_table text) returns void as $$
declare
r text;
cur_type text;
begin
raise notice 'NOTICE smth: %', 1;
for r in (select column_name from information_schema.columns where table_name = my_table) loop
raise notice 'NOTICE r: %', 2;
execute 'select data_type from ' -- ERROR here
|| quote_ident(columns_types_table)
|| ' where column_name = '
|| quote_ident(r)
into strict cur_type;
raise notice 'NOTICE cur_type: %', 3;
execute 'alter table '
|| quote_ident(my_table)
|| ' alter column '
|| quote_ident(r)
||' type '
|| quote_ident(cur_type)
|| ' using '
|| r
|| '::'
|| cur_type;
end loop;
end
$$
language 'plpgsql';
My ERROR:
ERROR: column "id" does not exist
Where: PL/pgSQL function change_columns(text,text) line 9 at EXECUTE
Function request:
select change_columns('test', 'col_types');
The full error message (at least in Postgres 14) is
ERROR: column "id" does not exist
LINE 1: select data_type from col_types where column_name = id
^
QUERY: select data_type from col_types where column_name = id
CONTEXT: PL/pgSQL function change_columns(text,text) line 9 at EXECUTE
which makes it easy to see where you went wrong: id is treated as an identifier here. You actually wanted to run the query
select data_type from col_types where column_name = 'id'
-- ^ ^
To generate this, you need to use quote_literal instead of quote_identifier:
execute 'select data_type from '
|| quote_ident(columns_types_table)
|| ' where column_name = '
|| quote_literal(r)
into strict cur_type;
(online demo. Notice I also had to change the alter column statement not to escape the type name)
An even better approach would be to use a parameterised query with a USING clause:
execute 'select data_type from '
|| quote_ident(columns_types_table)
|| ' where column_name = $1'
into strict cur_type
using r;
(online demo)

Update Null columns to Zero dynamically in Redshift

Here is the code in SAS, It finds the numeric columns with blank and replace with 0's
DATA dummy_table;
SET dummy_table;
ARRAY DUMMY _NUMERIC_;
DO OVER DUMMY;
IF DUMMY=. THEN DUMMY=0;
END;
RUN;
I am trying to replicate this in Redshift, here is what I tried
create or replace procedure sp_replace_null_to_zero(IN tbl_nm varchar) as $$
Begin
Execute 'declare ' ||
'tot_cnt int := (select count(*) from information_schema.columns where table_name = ' || tbl_nm || ');' ||
'init_loop int := 0; ' ||
'cn_nm varchar; '
Begin
While init_loop <= tot_cnt
Loop
Raise info 'init_loop = %', Init_loop;
Raise info 'tot_cnt = %', tot_cnt;
Execute 'Select column_name into cn_nm from information_schema.columns ' ||
'where table_name ='|| tbl_nm || ' and ordinal_position = init_loop ' ||
'and data_type not in (''character varying'',''date'',''text''); '
Raise info 'cn_nm = %', cn_nm;
if cn_nm is not null then
Execute 'Update ' || tbl_nm ||
'Set ' || cn_nm = 0 ||
'Where ' || cn_nm is null or cn_nm =' ';
end if;
init_loop = init_loop + 1;
end loop;
End;
End;
$$ language plpgsql;
Issues I am facing
When I pass the Input parameter here, I am getting 0 count
tot_cnt int := (select count(*) from information_schema.columns where table_name = ' || tbl_nm || ');'
For testing purpose I tried hardcode the table name inside proc, I am getting the error amazon invalid operation: value for domain information_schema.cardinal_number violates check constraint "cardinal_number_domain_check"
Is this even possible in redshift, How can I do this logic or any other workaround.
Need Expertise advise here!!
You can simply run an UPDATE over the table(s) using the NVL(cn_nm,0) function
UPDATE tbl_raw
SET col2 = NVL(col2,0);
However UPDATE is a fairly expensive operation. Consider just using a view over your table that wraps the columns in NVL(cn_nm,0)
CREATE VIEW tbl_clean
AS
SELECT col1
, NVL(col2,0) col2
FROM tbl_raw;

Concat text variables in postgresql function

I have this code and I want to concatenate the variables but don't work.
This is my DDL code for the view:
CREATE OR REPLACE function acd.add_credito2()
RETURNS void
SET SCHEMA 'acd'
SET search_path = acd
AS $$
DECLARE
auxsigla text;
auxnome text;
_sql text := 'CREATE OR REPLACE VIEW acd.teste AS SELECT md.matriz_disciplina_id AS id, dcp.nome, mc.curso, mc.versao AS matriz';
_join text := ' FROM matriz_disciplina as md LEFT JOIN disciplina as dcp ON md.disciplina_id = dcp.disciplina_id LEFT JOIN matriz_curricular as mc ON md.matriz_curricular_id = mc.matriz_curricular_id';
BEGIN
select into auxsigla, auxnome from ( select sigla, nome from acd.categoria_credito where categoria_credito_id = 9) as foo;
_join := _join || ' LEFT JOIN (SELECT creditos, matriz_disciplina_id FROM acd.disciplina_credito WHERE categoria_credito_id = ' || x || ') AS ' || "auxsigla" ' ON ' || "auxsigla" || '.matriz_disciplina_id = md.matriz_disciplina_id';
_sql := _sql || ', ' || "auxsigla" || '.' || auxnome || ' AS ' || auxnome;
_sql := _sql || _join;
EXECUTE _sql;
END;
$$ LANGUAGE plpgsql
So, when I execute the function
database-1=# select acd.add_credito2();
This error appears:
ERROR: type "auxsigla" does not exist
LINE 1: ...WHERE categoria_credito_id = ' || x || ') AS ' || "auxsigla"...
^
QUERY: SELECT _join || ' LEFT JOIN (SELECT creditos, matriz_disciplina_id FROM acd.disciplina_credito WHERE categoria_credito_id = ' || x || ') AS ' || "auxsigla" ' ON ' || "auxsigla" || '.matriz_disciplina_id = md.matriz_disciplina_id'
CONTEXT: PL/pgSQL function add_credito2() line 13 at assignment
Can anyone help me? I don't know what to do now.
(I know, this study view don't have a purpose but this is the idea that I want to use in the real view)
The error comes from this construct:
"auxsigla" ' ON '
You forgot a concatenation operator || between these two tokens, and now the SQL parser interprets it as
data_type string_constant
which is a way to specify constants of a certain data type.
Working examples would be DATE '2018-09-20' or INTEGER '-20'.
Your function has numerous other problems, two of which I could spot:
select into auxsigla, auxnome from will always set the variables to NULL because you forgot to specify which columns you want to select.
you do not properly escape single quotes while composing your dynamic query string. What if auxsigla has the value with'quote?
Use format() or quote_literal() and quote_ident() for that.

Postgresql function return multiple select statements

Can any one of you tell me how to approach this:
CREATE OR REPLACE FUNCTION name()
RETURNS ????? AS
$func$
BEGIN
SELECT * FROM tbl_a a;
SELECT * FROM tbl_b b;
END
$func$ LANGUAGE plpgsql;
Both tables have different structures.
You can use cursors but I can hardly imagine why you need such a function.
CREATE OR REPLACE FUNCTION my_multiselect(refcursor, refcursor) RETURNS VOID AS
$func$
BEGIN
OPEN $1 FOR SELECT * FROM information_schema.routines;
OPEN $2 FOR SELECT * FROM information_schema.sequences;
END
$func$ LANGUAGE plpgsql;
BEGIN;
SELECT my_multiselect('first_cursor_to_routines', 'second_cursor_to_sequences');
FETCH ALL IN first_cursor_to_routines;
FETCH ALL IN second_cursor_to_sequences;
COMMIT;
I'm not really sure what you're doing with this, but it sounds like you just want to return a union of these distinct result sets. You can do this with a dynamic query. I'm using Postgres 9.4.
CREATE OR REPLACE FUNCTION make_query(IN p_tables text[])
RETURNS void AS
$BODY$
DECLARE
v_qry text;
v_cols text;
v_types text;
v_as text;
BEGIN
EXECUTE format('
WITH sub AS (
SELECT
table_name,
column_name,
data_type
FROM
information_schema.columns
WHERE
table_name = ANY(%L)
ORDER BY
table_name,
ordinal_position)
,sub2 AS(
SELECT
DISTINCT ON (column_name, data_type)
column_name || '' '' || data_type AS def
FROM
sub
)
SELECT
string_agg(def, '','')
FROM
sub2;
',
p_tables
) INTO v_types;
v_qry := '
CREATE OR REPLACE FUNCTION name()
RETURNS TABLE(' || v_types || ') AS
$func$';
FOR i IN 1..array_upper(p_tables, 1)
LOOP
v_as := 'tbl' || i;
EXECUTE format('
WITH sub AS (
SELECT
table_name,
column_name,
data_type
FROM
information_schema.columns
WHERE
table_name = ANY(%L)
ORDER BY
table_name,
ordinal_position)
,sub2 AS(
SELECT
DISTINCT ON (column_name, data_type)
CASE WHEN table_name = ''%I''
THEN %L || ''.'' || column_name
ELSE ''NULL::'' || data_type
END AS cols
FROM
sub
)
SELECT
string_agg(cols, '','')
FROM
sub2;
',
p_tables,
p_tables[i],
v_as
) INTO v_cols;
IF i > 1 THEN
v_qry := v_qry || '
UNION ALL';
END IF;
v_qry := v_qry || '
SELECT ' || v_cols || ' FROM ' || p_tables[i] || ' AS ' || v_as;
IF i = array_upper(p_tables, 1) THEN
v_qry := v_qry || ';';
END IF;
END LOOP;
v_qry := v_qry || '
$func$ LANGUAGE sql;
';
EXECUTE v_qry;
END;
$BODY$
LANGUAGE plpgsql VOLATILE;
Sorry it looks ugly here, but this formatting helps the final product look nicer. If you're shy about executing a dynamic query like this off the bat, just replace EXECUTE v_qry; with RAISE INFO 'v_qry: %', v_qry; and it will simply print the dynamic query out in a message without executing it, so you can review what it will do once executed.
Then execute make_query() with a list of tables you want to display like this:
SELECT make_query(ARRAY['tbl_a', 'tbl_b']);
The result is that you will now have a function called name() which you can call in order to see the results of both tables at the same time, with all the union details already sorted out:
SELECT * FROM name();

PostgreSQL ERROR: EXECUTE of SELECT ... INTO is not implemented

When I run the following command from a function I defined, I get the error "EXECUTE of SELECT ... INTO is not implemented". Does this mean the specific command is not allowed (i.e. "SELECT ...INTO")? Or does it just mean I'm doing something wrong? The actual code causing the error is below. I apologize if the answer is already out here, however I looked and could not find this specific error. Thanks in advance... For whatever it's worth I'm running 8.4.7
vCommand = 'select ' || stmt.column_name || ' as id ' ||
', count(*) as nCount
INTO tmpResults
from ' || stmt.table_name || '
WHERE ' || stmt.column_name || ' IN (select distinct primary_id from anyTable
WHERE primary_id = ' || stmt.column_name || ')
group by ' || stmt.column_name || ';';
EXECUTE vCommand;
INTO is ambiguous in this use case and then is prohibited there.
You can use a CREATE TABLE AS SELECT instead.
CREATE OR REPLACE FUNCTION public.f1(tablename character varying)
RETURNS integer
LANGUAGE plpgsql
AS $function$
begin
execute 'create temp table xx on commit drop as select * from '
|| quote_ident(tablename);
return (select count(*) from xx);
end;
$function$
postgres=# select f1('omega');
f1
────
2
(1 row)