I am creating function which return the select query result from it. The details as shown below in the example:
Example:
Create or replace function fun_test(cola text,colb text,rel text)
returns table(columna text,columnb text)as
$Body$
Declare
table_name varchar :='Table_';
Begin
table_name := table_name || rel;
return query select distinct || quote_ident(cola) ||,||quote_ident(colb)|| from || quote_ident(table_name) ;
end;
$Body$
language plpgsql;
Error:
ERROR: syntax error at or near "||"
LINE 10: ...| quote_ident(cola) ||,||quote_ident(colb)|| from || quote_i...
^
You're trying to construct a query dynamically, but you're not using EXECUTE. That won't work. You can't just put arbitrary expressions in place of identifiers, like:
return query select distinct || quote_ident(cola) ||,||quote_ident(colb)|| from || quote_ident(table_name) ;
which is why you're getting the error at:
from ||
^
as that's syntactically invalid nonsense.
Instead I think you want:
RETURN QUERY EXECUTE 'select distinct ' || quote_ident(cola) ||', '||quote_ident(colb)||' from '|| quote_ident(table_name);
which is better written as:
RETURN QUERY EXECUTE format('select distinct %I, %I from %I', cola, colb, table_name);
Related
I'm trying to write a function which executes a dynamically prepared sql query and return the result as table.
I was refering to the SO answer, it mentioned to use language plpgsql, even after using it I'm getting the same syntax error.
Below is the function code provided.
CREATE OR REPLACE FUNCTION public.execute_test(
ddsmappingids text,
totalnumberofrecords bigint,
skiprecords bigint,
pagesize integer,
cid bigint)
RETURNS TABLE(sampletime timestamp without time zone, jsonstring text, rowscount bigint)
LANGUAGE 'plpgsql'
COST 100
VOLATILE PARALLEL UNSAFE
ROWS 1000
AS $BODY$
DECLARE
table_names text:='dynamictable';
sql_query text;
dsids_array int[];
sub_query text;
BEGIN
if cid>=2 then
select 'dynamictable_'||cid into table_names;
end if;
select string_to_array(ddsmappingids, ',')::int[] into dsids_array;
sub_query:='SELECT * , COUNT(*) over() AS row_count FROM (SELECT start_time, cast(jsonb_object_agg(vw.dataseries_name, ROUND(CAST(o.dbl_value as numeric), 4)) as text) AS DataSeriesValue
FROM ' || quote_ident(table_names) ||' o
join vwdds vw on o.ddmid=vw.id
where ddmid in (' || array_to_string(dsids_array,',') || ')
and o.dbl_value is not null
GROUP BY start_time
ORDER BY start_time desc
limit ' || totalnumberofrecords || ') t offset '|| skiprecords || ' rows fetch next ' || pagesize || ' rows only;';
RAISE NOTICE 'Temporary table created';
RETURN QUERY Execute sub_query;
END
$BODY$;
Error Message when running the function
EXECUTE command, when i try with some simple query it is working fine, but the query mentioned in the code snippet it is giving syntax error.
Please help me where I'm doing wrong.
I am a newbie wrt functions and I am struggling with using the name of a table in the function body. I get an error "SQL Error [42703]: ERROR: column "tname" does not exist" when I call the function using
select "JsonToView"('data_import.import_360xero_report');
My code is below
create or replace
function data_import."JsonToView"(tname text) returns numeric
language plpgsql
as $function$
begin
do
$$
declare
l_keys text;
begin
drop view if exists v_json_view cascade;
select
string_agg(distinct format('import_data ->> %L as %I', jkey, jkey), ', ')
into
l_keys
from
import_360xero_report,
json_object_keys(import_data) as t(jkey);
execute 'create view v_json_view as select ' || l_keys || ' from ' || tname;
end;
$$;
return 0;
end $function$ ;
I have modified the code and the second create view query works with the table name but the first one does not.
Below if my modified code
create or replace
function data_import."JsonToView"(tname text) returns numeric
language plpgsql
as $function$
declare
l_keys text;
begin
drop view if exists v_json_view cascade;
execute $a$select
string_agg(distinct format('import_data ->> %L as %I', jkey, jkey), ', ')
into
l_keys
from $a$ ||
tname || $b$,
json_object_keys(import_data) as t(jkey)$b$;
execute 'create view v_json_view as select ' || l_keys || ' from ' || tname;
return 0;
end $function$ ;
The error I am getting is
SQL Error [0A000]: ERROR: EXECUTE of SELECT ... INTO is not implemented
Hint: You might want to use EXECUTE ... INTO or EXECUTE CREATE TABLE ... AS instead.
Where: PL/pgSQL function "JsonToView"(text) line 10 at EXECUTE
The problem is the superfluous nested DO statement.
The variable tname exists only in the scope of the function, not in the nested DO statement. DO is an SQL statement, not a PL/pgSQL statement, and there are no variables in SQL. Also, DO does not allow parameters.
Get rid of the DO and you will be fine.
I am trying to write a plpgsql procedure to perform spatial tiling of a postGIS table. I can perform the operation successfully using the following procedure in which the table names are hardcoded. The procedure loops through the tiles in tile_table and for each tile clips the area_table and inserts it into split_table.
CREATE OR REPLACE PROCEDURE splitbytile()
AS $$
DECLARE
tile RECORD;
BEGIN
FOR tile IN
SELECT tid, geom FROM test_tiles ORDER BY tid
LOOP
INSERT INTO split_table (id, areaname, ttid, geom)
SELECT id, areaname, tile.tid,
CASE WHEN st_within(base.geom, tile.geom) THEN st_multi(base.geom)
ELSE st_multi(st_intersection(base.geom, tile.geom)) END as geom
FROM area_table as base
WHERE st_intersects(base.geom, tile.geom);
COMMIT;
END LOOP;
END;
$$ LANGUAGE 'plpgsql';
Having tested this successfully, now I need to convert it to a dynamic procedure where I can provide the table names as parameters. I tried the following partial conversion, using format() for inside of loop:
CREATE OR REPLACE PROCEDURE splitbytile(in_table text, grid_table text, split_table text)
AS $$
DECLARE
tile RECORD;
BEGIN
FOR tile IN
EXECUTE format('SELECT tid, geom FROM %I ORDER BY tid', grid_table)
LOOP
EXECUTE
FORMAT(
'INSERT INTO %1$I (id, areaname, ttid, geom)
SELECT id, areaname, tile.tid,
CASE WHEN st_within(base.geom, tile.geom) THEN st_multi(base.geom)
ELSE st_multi(st_intersection(base.geom, tile.geom)) END as geom
FROM %2$I as base
WHERE st_intersects(base.geom, tile.geom)', split_table, in_table
);
COMMIT;
END LOOP;
END;
$$ LANGUAGE 'plpgsql';
But it throws an error
missing FROM-clause entry for table "tile"
So, how can I convert the procedure to a dynamic one? More specifically, how can I use the record data type (tile) returned by the for loop inside the loop? Note that it works when format is not used.
You can use EXECUTE ... USING to supply parameters to a dynamic query:
EXECUTE
format(
'SELECT r FROM %I WHERE c = $1.val',
table_name
)
INTO result_var
USING record_var;
The first argument to USING will be used for $1, the second for $2 and so on.
See the documentation for details.
Personally I use somehow different way to create dynamic functions. By concatination and execute function. You can also do like this.
CREATE OR REPLACE FUNCTION splitbytile()
RETURNS void AS $$
declare
result1 text;
table_name text := 'test_tiles';
msi text := '+7 9912 231';
msi text := 'Hello world';
code text := 'code_name';
_operator_id integer := 2;
begin
query1 := 'SELECT msisdn from ' || table_name || ' where msisdn = ''' || msi::text ||''';';
query2 := 'INSERT INTO ' || table_name || '(msisdn,usage,body,pr_code,status,sent_date,code_type,operator_id)
VALUES( ''' || msi::text || ''',' || true || ',''' || _body::text || ''',''' || code::text || ''',' || false || ',''' || time_now || ''',' || kod_type || ',' || _operator_id ||');';
execute query1 into result1;
execute query2;
END;
$function$
You just make your query as text then anywhere you want you can execute it. Maybe by checking result1 value inside If statement or smth like that.
I'm trying to create function with result of concatenated value.
see below:
CREATE OR REPLACE FUNCTION select_name()
RETURNS TABLE(name text ) AS
$BODY$
BEGIN
RETURN QUERY
select
cast(first_name as text) ||' ' || cast( middle_name as text) ||' ' || cast(last_name as text) as name
from table_name;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100
ROWS 1000;
However upon querying
select * from select_name();
it shows error:
ERROR: relation "select_name" does not exist
LINE 8: select * from select_name
^
********** Error **********
ERROR: relation "select_name" does not exist
SQL state: 42P01
Character: 159
I'm stuck here.
Please help.
I tried to used below statement, and it worked. ^_^
select
cast( first_name ||' ' || middle_name ||' ' || last_name as text) as name
from table_name;
Try this out this will go like a fly.
CREATE OR REPLACE FUNCTION select_name()
RETURNS TABLE(name text ) AS
$$
BEGIN
RETURN QUERY
select
select
cast(first_name as text) ||' ' || cast( middle_name as text) ||' ' || cast(last_name as text) as name
from table_name;
END;
$$ LANGUAGE plpgsql;
EDIT
It seems my issue is when this select statement returns null (which is the case I'm trying to handle - when it returns null, I want my new value to be -999). How can I go about doing this if it errors out whenever a null is found?
ORIGINAL
I have read every other SO post I could find regarding this error, but none of which seemed to address the root of my issue.
The error is pretty straightforward - one of my arguments within my EXECUTE statement is null. Great. However, I print out each of the values that make up my EXECUTE statement right before it gets called, and I can clearly see that none of the values are null.
Code:
CREATE FUNCTION inform_icrm_prob_flow_query(tablename text, location_id int,
product_date_str text, lead_time_start int,
lead_time_end int, first_member_id int,
last_member_id int, dest_file text)
RETURNS void AS $$
DECLARE
count int;
product_date TIMESTAMPTZ;
interval_lead_time_start text;
interval_lead_time_end text;
curr_value double precision;
query text;
BEGIN
product_date := product_date_str::TIMESTAMPTZ;
count := first_member_id;
curr_value := 0;
interval_lead_time_start := ''''|| product_date ||'''::timestamptz +
interval '''||lead_time_start||' hours''';
interval_lead_time_end := ''''|| product_date ||'''::timestamptz +
interval '''||lead_time_end||' hours'' -
interval ''6 hours''';
--create our temporary table and populate it's date column
EXECUTE 'CREATE TEMPORARY TABLE temp_table_icrm_prob_flow AS
SELECT * FROM generate_series('||interval_lead_time_start || ',' ||
interval_lead_time_end || ', ''6 hours'')
AS date_valid';
LOOP
EXIT WHEN count > last_member_id;
IF NOT EXISTS(
SELECT 'date_valid'
FROM information_schema.columns
WHERE table_name='temp_table_icrm_prob_flow'
and column_name='value'||count||'')
THEN
EXECUTE 'ALTER TABLE temp_table_icrm_prob_flow ADD COLUMN value' || count
|| ' double precision DEFAULT -999';
END IF;
raise notice 'tablename: %', tablename;
raise notice 'location_id: %', location_id;
raise notice 'product_date: %', product_date;
raise notice 'count: %', count;
query := 'SELECT value FROM '|| tablename ||'
INNER JOIN temp_table_icrm_prob_flow
ON (temp_table_icrm_prob_flow.date_valid = '|| tablename ||'.date_valid)
WHERE '|| tablename ||'.id_location = '|| location_id ||'
AND '|| tablename ||'.date_product = '''|| product_date ||'''
AND '|| tablename ||'.id_member = '|| count ||'';
EXECUTE query INTO curr_value;
EXECUTE 'UPDATE temp_table_icrm_prob_flow
SET value'|| count ||' = COALESCE('|| curr_value ||', -999)';
count := count + 1;
END LOOP;
EXECUTE 'ALTER TABLE temp_table_icrm_prob_flow DROP COLUMN date_valid';
EXECUTE 'COPY temp_table_icrm_prob_flow TO '''||dest_file||''' DELIMITER '','' CSV';
EXECUTE 'DROP TABLE temp_table_icrm_prob_flow';
END;
$$ LANGUAGE plpgsql;
Output:
NOTICE: tablename: inform_tseries_data_basin_proc_fcst_prob_flow
NOTICE: location_id: 38
NOTICE: product_date: 2015-02-05 12:00:00+00
NOTICE: count: 1
ERROR: query string argument of EXECUTE is null
CONTEXT: PL/pgSQL function inform_icrm_prob_flow_query(text,integer,text,integer,integer,integer,integer,text) line 38 at EXECUTE
If none of the variables I am passing in are null, and the only other thing referenced is a temp table that I know exists, what could be causing this error?
Note: when changing my query to:
query := 'SELECT value FROM '|| tablename ||' WHERE '|| tablename ||'.id_location = '|| location_id ||' AND '|| tablename ||'.date_product = '''|| product_date ||''' AND '|| tablename ||'.id_member = '|| count ||' AND temp_table_icrm_prob_flow.date_va lid = '|| tablename ||'.date_valid';
I get the following error:
NOTICE: tablename: inform_tseries_data_basin_proc_fcst_prob_flow
NOTICE: location_id: 38
NOTICE: product_date: 2015-02-05 12:00:00+00
NOTICE: count: 1
ERROR: missing FROM-clause entry for table "temp_table_icrm_prob_flow"
LINE 1: ..._data_basin_proc_fcst_prob_flow.id_member = 1 AND temp_table...
^
QUERY: SELECT value FROM inform_tseries_data_basin_proc_fcst_prob_flow WHERE inform_tseries_data_basin_proc_fcst_prob_flow.id_location = 38 AND inform_tseries_data_basin_proc_fcst_prob_flow.date_product = '2015-02-05 12:00:00+00' AND inform_tseries_data_basin_proc_fcst_prob_flow.id_member = 1 AND temp_table_icrm_prob_flow.date_valid = inform_tseries_data_basin_proc_fcst_prob_flow.date_valid
CONTEXT: PL/pgSQL function inform_icrm_prob_flow_query(text,integer,text,integer,integer,integer,integer,text) line 35 at EXECUTE
Sorry for small offtopic. Your code is pretty unreadable (and SQL injecttion vulnerable). There are some techniques, that you can use:
Use clause USING of EXECUTE statement for usual parameters.
DO $$
DECLARE
tablename text := 'mytab';
from_date date := CURRENT_DATE;
BEGIN
EXECUTE 'INSERT INTO ' || quote_ident(tablename) || ' VALUES($1)'
USING from_date;
END
$$;
This code will be safe (due using quote_ident function), little bit faster (due using binary value of from_date variable - removed multiple string<->date conversions and little bit more readable (because string expression is shorter).
Use function format. The building query string will be shorter and more readable (table aliases helps too):
query := format('
SELECT value
FROM %I _dtn
INNER JOIN temp_table_icrm_prob_flow t ON t.date_valid = _dtn.date_valid
WHERE _dtn.id_location = $1
AND _dtn.date_product = $2
AND _dtd.id_member = $3'
, tablename);
EXECUTE query INTO curr_value USING location_id, product_date, count;
Using variables named like important SQL keywords and identifier is wrong idea - names count, values are wrong.
The error message is clean - you are using the identifier temp_table_icrm_prob_flow.date_valid, but the table temp_table_icrm_prob_flow is not mentioned in query. The query missing JOIN part.