Query table within variable schemanames - sql

I want to run a query of a table within variable schemas.
I have a postgresql db that I've written the following query for:
SELECT
project_id, project_name, schema_p
FROM public.projects
JOIN public.schema_ps
ON public.schema_ps.root_id = public.projects.project_id
ORDER BY project_id ASC
The schema_p column contains the names of schemas that all have a table named com_set that I need to query as follows:
SELECT dev_id, dev_name FROM [variable_schama_name].com_set
What I'd like to do is write a query to generate a single combined result, where my resulting dataset would contain the columns of project_id, project_name, schema_p, dev_id, and dev_name. This would mean I'd have repeats in the first three columns and unique entries in the second last two columns. One way to think of it is that I'd like to run the first query to get the names of the schemas, then run the second query on each of the schemas.
Hopefully that all makes sense. Thanks for the help!

A possible solution relies on a dynamic query without guarantee about the performance :
CREATE OR REPLACE FUNCTION my_query(OUT project_id int, OUT project_name text, OUT schema_p text, OUT dev_id int, OUT dev_name text)
RETURNS setof record LANGUAGE plpgsql AS $$
DECLARE
txt text ;
BEGIN
SELECT string_agg(
'SELECT p.project_id, p.project_name, s.schema_p, c.dev_id, c.dev_name
FROM public.projects AS p
INNER JOIN public.schema_ps AS s
ON s.root_id = p.project_id
CROSS JOIN ' || ps.schema_p || '.com_set AS c', ' UNION ALL ')
|| ' ORDER BY project_id ASC'
FROM public.schema_ps AS ps
INTO txt ;
RETURN QUERY EXECUTE txt ;
END ; $$ ;
and then you just call my_query :
SELECT my_query() ;

Related

Oracle function with select all from tables

SELECT DISTINCT L.* FROM LABALES L , MATCHES M
WHERE M.LIST LIKE '%ENG'
ORDER BY L.ID
I need to create function with this select, I tried this but it doesn't work.
CREATE OR REPLACE FUNCTION getSoccerLists
RETURN varchar2 IS
list varchar2(2000);
BEGIN
SELECT DISTINCT L.* FROM LABALES L , MATCHES M
WHERE M.LIST LIKE '%ENG'
ORDER BY L.ID
return list;
END;
How will I create function that returns all from table L.
Thanks
You may use implicit result using DBMS_SQL.RETURN_RESULT(Oracle12c and above) in a procedure using a cursor to your query.
CREATE OR REPLACE PROCEDURE getSoccerLists
AS
x SYS_REFCURSOR;
BEGIN
OPEN x FOR SELECT DISTINCT L.* FROM LABALES L
JOIN MATCHES M ON ( 1=1 ) -- join condition
WHERE M.LIST LIKE '%ENG'
ORDER BY L.ID;
DBMS_SQL.RETURN_RESULT(x);
END;
/
then simply call the procedure
EXEC getSoccerLists;
For lower versions(Oracle 11g) , you may use a print command to display the cursor's o/p passing ref cursor as out parameter.
CREATE OR REPLACE PROCEDURE getSoccerLists (x OUT SYS_REFCURSOR)
AS
BEGIN
OPEN x FOR SELECT DISTINCT L.* FROM LABALES L
JOIN MATCHES M ON ( 1=1 ) -- join condition
WHERE M.LIST LIKE '%ENG'
ORDER BY L.ID;
END;
/
Then, in SQL* Plus or running as script in SQL developer and Toad, you may get the results using this.
VARIABLE r REFCURSOR;
EXEC getSoccerLists (:r);
PRINT r;
Another option is to use TABLE function by defining a collection of the record type of the result within a package.
Refer Create an Oracle function that returns a table
I guess this questions is a repetition of the your previously asked question, where you wanted to get all the columns of tables but into separate column. I already answered in stating this you cannot do if you call your function via a SELECT statement. If you call your function in a Anoymous block you can display it in separate columns.
Here Oracle function returning all columns from tables
Alternatively, you can get the results separated by a comma(,) or pipe (|) as below:
CREATE OR REPLACE
FUNCTION getSoccerLists
RETURN VARCHAR2
IS
list VARCHAR2(2000);
BEGIN
SELECT col1
||','
||col2
||','
||col2
INTO LIST
FROM SOCCER_PREMATCH_LISTS L ,
SOCCER_PREMATCH_MATCHES M
WHERE M.LIST LIKE '%' || (L.SUB_LIST) || '%'
AND (TO_TIMESTAMP((M.M_DATE || ' ' || M.M_TIME), 'DD.MM.YYYY HH24:MI') >
(SELECT SYSTIMESTAMP AT TIME ZONE 'CET' FROM DUAL
))
ORDER BY L.ID");
Return list;
End;
Note here if the column size increased 2000 chars then again you will lose the data.
Edit:
From your comments
I want it to return a table set of results.
You then need to create a table of varchar and then return it from the function. See below:
CREATE TYPE var IS TABLE OF VARCHAR2(2000);
/
CREATE OR REPLACE
FUNCTION getSoccerLists
RETURN var
IS
--Initialization
list VAR :=var();
BEGIN
SELECT NSO ||',' ||NAME BULK COLLECT INTO LIST FROM TEST;
RETURN list;
END;
Execution:
select * from table(getSoccerLists);
Note: Here in the function i have used a table called test and its column. You replace your table with its columnname.
Edit 2:
--Create a object with columns same as your select statement
CREATE TYPE v_var IS OBJECT
(
col1 NUMBER,
col2 VARCHAR2(10)
)
/
--Create a table of your object
CREATE OR REPLACE TYPE var IS TABLE OF v_var;
/
CREATE OR REPLACE FUNCTION getSoccerLists
RETURN var
IS
--Initialization
list VAR :=var();
BEGIN
--You above object should have same columns with same data type as you are selecting here
SELECT v_var( NSO ,NAME) BULK COLLECT INTO LIST FROM TEST;
RETURN list;
END;
Execution:
select * from table(getSoccerLists);
This is not an answer on how to build a function for this, as I'd recommend to make this a view instead:
CREATE OR REPLACE VIEW view_soccer_list AS
SELECT *
FROM soccer_prematch_lists l
WHERE EXISTS
(
SELECT *
FROM soccer_prematch_matches m
WHERE m.list LIKE '%' || (l.sub_list) || '%'
AND TO_TIMESTAMP((m.m_date || ' ' || m.m_time), 'DD.MM.YYYY HH24:MI') >
(SELECT SYSTIMESTAMP AT TIME ZONE 'CET' FROM DUAL)
);
Then call it in a query:
SELECT * FROM view_soccer_list ORDER BY id;
(It makes no sense to put an ORDER BY clause in a view, because you access the view like a table, and table data is considered unordered, so you could not rely on that order. The same is true for a pipelined function youd access with FROM TABLE (getSoccerLists). Always put the ORDER BY clause in your final queries instead.)

how to get table name from column value in oracle sql?

I have a main table that has two columns with table names and id's. And I have those tables with table names in my DB.
For example, I find particular table name, selecting id. And then I want to populate table with that name with data. And I want to do that in one query. How I can do that?
The goal: to populate with data all tables at once, that has the names that similar with values in table name column from main table.
That is how I'm getting the list of tables. I should probably loop through it.
select tbl from asp_tbl where asp in (
select id from (
SELECT * FROM DIMENSION WHERE EXTERNALKEY LIKE 'W16%')
);
And then I will try to merge the data from other tables inside the table that needs to be populated:
MERGE INTO tbl d
USING
(SELECT ? nums, ? names from data_table) s
ON(d.product = s.product and d.ga = s.ga and d.metric_id = s.metric_id)
WHEN MATCHED THEN UPDATE SET d.names = s.names
WHEN NOT MATCHED THEN INSERT (nums, names)values(s.nums,s.names);
Did I provide enough info?
As I understand you need some stored procedure witch may fulfil a table with some test data. If so you may write something like:
create procedure fulfil_test_data (p_table_name varchar2) is
begin
for x IN (select tbl from asp_tbl where asp in (
SELECT table_id FROM DIMENSION WHERE EXTERNALKEY LIKE p_table_name )) loop
execute immediate 'insert into '|| x.tbl ||' (nums, names)
select level , chr(ascci(''A'') + mod(level,26)) from dual connect by level < 1001';
end loop;
end;
/
And call it
begin
fulfil_test_data('W16%');
end;
/

Select a row and insert it with different IDs n times

I am trying to come up with a script in Postgres that will select the first row in a table and insert that row x number of times back into the same table.
Here is what I have:
INSERT INTO campaign (select column_name from campaign)
SELECT x.id from generate_series(50, 500) as x(id);
The above obviously doesn't work.
Just get the syntax for the INSERT statement right:
INSERT INTO campaign (id, column_name)
SELECT g.g, t.column_name
FROM (SELECT column_name FROM campaign LIMIT 1) t -- picking arbitrary row
,generate_series(50, 500) g(g); -- 451 times
The CROSS JOIN to generate_series() multiplies each selected row.
Selecting one arbitrary row, since the question didn't define "first". There is no natural order in a table. To pick a certain row, add ORDER BY and/or WHERE.
There is no syntactical shortcut to select all columns except the one named "id". You have to use the complete row or provide a list of selected columns.
Automation with dynamic SQL
To get around this, build the query string from catalog tables (or the information schema) and use EXECUTE in a plpgsql function (or some other procedural language). Only using pg_attribute.
format() requires Postgres 9.1 or later.
CREATE OR REPLACE FUNCTION f_multiply_row(_tbl regclass
, _idname text
, _minid int
, _maxid int)
RETURNS void AS
$func$
BEGIN
EXECUTE (
SELECT format('INSERT INTO %1$s (%2$I, %3$s)
SELECT g.g, %3$s
FROM (SELECT * FROM %1$s LIMIT 1) t
,generate_series($1, $2) g(g)'
, _tbl
, _idname
, string_agg(quote_ident(attname), ', ')
)
FROM pg_attribute
WHERE attrelid = _tbl
AND attname <> _idname -- exclude id column
AND NOT attisdropped -- no dropped (dead) columns
AND attnum > 0 -- no system columns
)
USING _minid, _maxid;
END
$func$ LANGUAGE plpgsql;
Call in your case:
SELECT f_multiply_row('campaign', 'id', 50, 500);
SQL Fiddle.
Major points
Properly escape identifiers to avoid SQL injection. Using format() and regclass for the table name. Details:
Table name as a PostgreSQL function parameter
_idname is the column name to exclude ('id' in your case). Case sensitive!
Pass values in the USING clause. $1 and $2 in generate_series($1, $2) reference those parameters (not the function parameters).
More explanation in related answers. Try a search:
https://stackoverflow.com/search?q=[plpgsql]+[dynamic-sql]+format+pg_attribute

Left join with dynamic table name derived from column

I am new in PostgreSQL and I wonder if it's possible to use number from table tbc as part of the table name in left join 'pa' || number. So for example if number is 456887 I want left join with table pa456887. Something like this:
SELECT tdc.cpa, substring(tdc.ku,'[0-9]+') AS number, paTab.vym
FROM public."table_data_C" AS tdc
LEFT JOIN concat('pa' || number) AS paTab ON (paTab.cpa = tdc.cpa)
And I want to use only PostgreSQL, not additional code in PHP for example.
Either way, you need dynamic SQL.
Table name as given parameter
CREATE OR REPLACE FUNCTION foo(_number int)
RETURNS TABLE (cpa int, nr text, vym text) AS -- adapt to actual data types!
$func$
BEGIN
RETURN QUERY EXECUTE format(
'SELECT t.cpa, substring(t.ku,'[0-9]+'), p.vym
FROM public."table_data_C" t
LEFT JOIN %s p USING (cpa)'
, 'pa' || _number
);
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM foo(456887)
Generally, you would sanitize table names with format ( %I ) to avoid SQL injection. With just an integer as dynamic input that's not necessary. More details and links in this related answer:
INSERT with dynamic table name in trigger function
Data model
There may be good reasons for the data model. Like partitioning / sharding or separate privileges ...
If you don't have such a good reason, consider consolidating multiple tables with identical schema into one and add the number as column. Then you don't need dynamic SQL.
Consider inheritance. Then you can add a condition on tableoid to only retrieve rows from a given child table:
SELECT * FROM parent_table
WHERE tableoid = 'pa456887'::regclass
Be aware of limitations for inheritance, though. Related answers:
Get the name of a row's source table when querying the parent it inherits from
Select (retrieve) all records from multiple schemas using Postgres
Name of 2nd table depending on value in 1st table
Deriving the name of the join table from values in the first table dynamically complicates things.
For only a few tables
LEFT JOIN each on tableoid. There is only one match per row, so use COALESCE.
SELECT t.*, t.tbl, COALESCE(p1.vym, p2.vym, p3.vym) AS vym
FROM (
SELECT cpa, ('pa' || substring(ku,'[0-9]+'))::regclass AS tbl
FROM public."table_data_C"
-- WHERE <some condition>
) t
LEFT JOIN pa456887 p1 ON p1.cpa = t.cpa AND p1.tableoid = t.tbl
LEFT JOIN pa456888 p2 ON p2.cpa = t.cpa AND p2.tableoid = t.tbl
LEFT JOIN pa456889 p3 ON p3.cpa = t.cpa AND p3.tableoid = t.tbl
For many tables
Combine a loop with dynamic queries:
CREATE OR REPLACE FUNCTION foo(_number int)
RETURNS TABLE (cpa int, nr text, vym text) AS
$func$
DECLARE
_nr text;
BEGIN
FOR _nr IN
SELECT DISTINCT substring(ku,'[0-9]+')
FROM public."table_data_C"
LOOP
RETURN QUERY EXECUTE format(
'SELECT t.cpa, _nr, p.vym
FROM public."table_data_C" t
LEFT JOIN %I p USING (cpa)
WHERE t.ku LIKE (_nr || '%')'
, 'pa' || _nr
);
END LOOP;
END
$func$ LANGUAGE plpgsql;

Concatenate multiple fields in query string in plpgsql

I am using plpgsql and hibernate and want to create a function which contains the query string given below. In the select clause I want to concatenate 3 fields but while running this query I am getting error message like:
ERROR: syntax error at or near "' '"
SQL state: 42601
Context: PL/pgSQL function "est_fn_dept_wise_emp_report" line 30 at open
I am new using stored functions, it might be a basic question but somehow I was unable to find a solution.
query1 = 'SELECT est_emp_empmaster.emp_no AS est_emp_empmaster_emp_no,
adm_m_department.dept_name AS adm_m_department_dept_name,
adm_m_subdepartment.sub_dept_id AS adm_m_subdepartment_sub_dept_id,
adm_m_subdepartment.sub_dept_name AS adm_m_subdepartment_sub_dept_name,
est_m_designation.desig_name AS est_m_designation_desig_name,
est_emp_empmaster.first_name'|| ' ' ||'est_emp_empmaster.middle_name'|| ' ' ||'est_emp_empmaster.surname AS empname
FROM public.adm_m_department adm_m_department
INNER JOIN public.adm_m_subdepartment adm_m_subdepartment
ON adm_m_department.dept_id = adm_m_subdepartment.dept_id
INNER JOIN public.est_emp_empmaster est_emp_empmaster
ON adm_m_department.dept_id = est_emp_empmaster.dept_id
AND adm_m_subdepartment.sub_dept_id = est_emp_empmaster.sub_dept_id
INNER JOIN public.est_emp_salary est_emp_salary
ON est_emp_empmaster.emp_no = est_emp_salary.emp_no
INNER JOIN public.est_m_designation est_m_designation
ON est_emp_salary.pre_desig_code = est_m_designation.desig_code
AND est_emp_salary.retired_flag ='|| quote_literal('N') ||'
WHERE est_emp_empmaster.corp_coun_id=0 or est_emp_empmaster.corp_coun_id is null or est_emp_empmaster.corp_coun_id = '|| quote_literal($1) ||'
ORDER BY adm_m_department.dept_id,adm_m_subdepartment.sub_dept_id,est_emp_empmaster.emp_no ASC';
OPEN refcur FOR
EXECUTE query1;
LOOP
FETCH refcur INTO return_record;
EXIT WHEN NOT FOUND;
RETURN NEXT return_record;
END LOOP;
CLOSE refcur;**
The above query runs fine if I execute it without executing through query string. But as I want to use this query for multiple conditions and in those condition I want to modify this query to get different results.
This can be much simpler, safer and faster (assuming at least Postgres 8.4):
CREATE OR REPLACE FUNCTION foo(_corp_coun_id int) -- guessing type
RETURNS TABLE (
emp_no int -- guessing data types ..
,dept_name text -- .. replace with actual types
,sub_dept_id int
,sub_dept_name text
,desig_name text
,empname text) AS
$func$
BEGIN
RETURN QUERY
SELECT em.emp_no
,dp.dept_name
,sb.sub_dept_id
,sb.sub_dept_name
,ds.desig_name
,concat_ws(' ', em.first_name, em.middle_name, em.surname) -- AS empname
FROM adm_m_department dp
JOIN adm_m_subdepartment su ON sb.dept_id = dp.dept_id
JOIN est_emp_empmaster em ON em.dept_id = sb.dept_id
AND em.sub_dept_id = sb.sub_dept_id
JOIN est_emp_salary sl ON sl.emp_no = em.emp_no
AND sl.retired_flag = 'N' -- untangled join cond.
JOIN est_m_designation ds ON ds.desig_code = sl.pre_desig_code
WHERE em.corp_coun_id = 0 OR
em.corp_coun_id IS NULL OR
em.corp_coun_id = $1
ORDER BY dp.dept_id, sb.sub_dept_id, em.emp_no;
END
$func$
LANGUAGE plpgsql SET search_path=public;
To address your primary question: use concat_ws() for simple and secure concatenation of multiple columns (doesn't fail with NULL).
You do not need dynamic SQL here since the variables are only values (not identifiers).
You do not need a CURSOR here.
You do not need a LOOP. RETURN QUERY does the same, simpler and faster.
You do not need column aliases, only the names of the OUT parameters (implicitly the column names in RETURNS TABLE (...)) are relevant.
Replace the multiple schema qualification public. in your query with a single SET search_path = public.
I also untangled your query, used short table aliases and reformatted to make it easier to read.
You don't even need plpgsql at all here. Can be a simpler SQL function:
CREATE OR REPLACE FUNCTION foo(_corp_coun_id int)
RETURNS TABLE (
emp_no int -- guessing data types ..
,dept_name text -- .. replace with actual types!
,sub_dept_id int
,sub_dept_name text
,desig_name text
,empname text) AS
$func$
SELECT em.emp_no
,dp.dept_name
,sb.sub_dept_id
,sb.sub_dept_name
,ds.desig_name
,concat_ws(' ', em.first_name, em.middle_name, em.surname) -- AS empname
FROM adm_m_department dp
JOIN adm_m_subdepartment sb ON sb.dept_id = dp.dept_id
JOIN est_emp_empmaster em ON em.dept_id = sb.dept_id
AND em.sub_dept_id = sb.sub_dept_id
JOIN est_emp_salary sl ON sl.emp_no = em.emp_no
AND sl.retired_flag = 'N' -- untangled join cond.
JOIN est_m_designation ds ON ds.desig_code = sl.pre_desig_code
WHERE em.corp_coun_id = 0 OR
em.corp_coun_id IS NULL OR
em.corp_coun_id = $1
ORDER BY dp.dept_id, sb.sub_dept_id, em.emp_no;
$func$
LANGUAGE sql SET search_path=public;
I found a solution to the above problem,
actually it was well working in normal query but i got problem while running it in dynamic query.
The solution to the above problem is as follows.Thanks again.. :)
est_emp_empmaster.first_name||'' ''||est_emp_empmaster.middle_name||'' ''||est_emp_empmaster.surname AS empname