I want to give all privileges to each table in the database。
sql as follows：
CREATE OR REPLACE FUNCTION test()
RETURNS void
AS $$
DECLARE
tb RECORD;
sql1 TEXT;
BEGIN
FOR tb IN (select tablename from pg_tables where schemaname='public')
LOOP
sql1 := 'GRANT ALL ON table ' || tb.tablename || ' TO tmp_admin';
EXECUTE sql1;
--RAISE NOTICE '%s', sql1;
END LOOP;
END
$$ LANGUAGE PLPGSQL;
select * FROM test();
when i RAISE NOTICE, it can normal output the sql i wanted。but this sql always effect。
but this sql always effect
I don't know what this means. Presumably you mean it doesn't do the right thing, otherwise you wouldn't have a question to ask.
As the horse mentioned, you don't to complicate this with a function at all. But regardless, it does work for me, as long as your table names don't need to be double-quoted. You should use FORMAT() rather than || to construct your string, to avoid that problem.
If you get an error, what is the error you get? If you think it silently has no effect, what did you do to infer the lack of effect?
Related
I am trying to create a function to create table backup dynamically.
But I am getting error like :
ERROR: syntax error at or near "'
Here's one of my approach, which I am trying:
CREATE OR REPLACE FUNCTION public.test () RETURNS varchar AS
$BODY$ DECLARE backup_string varchar(50);
BEGIN
backup_string = (SELECT '_'||LPAD(DATE_PART('DAY',CURRENT_DATE)::VARCHAR,2,'0')||DATE_PART('MONTH',CURRENT_DATE)::VARCHAR||DATE_PART('YEAR',CURRENT_DATE)::VARCHAR||'_1');
EXECUTE 'SELECT * INTO table_name'|| backup_string ||' FROM table_name';
RETURN 'Y';
EXCEPTION WHEN others THEN RETURN 'N';
END
; $BODY$
LANGUAGE 'plpgsql'
GO
SELECT * FROM test()
I am not getting, why that execute statement giving me error like that.
I suggest so simplify your code and make use of the format() function to generate the dynamic SQL. That way you can avoid the clutter that concatenation generates and you can concentrate on the actual SQL code. In addition to that it also properly deals with identifiers that might need quoting.
When dealing with dynamic SQL it's always a good idea to store the generated SQL statement in a variable, so that it can be printed for debugging purposes if you get an error. Looking at the generated SQL usually tells you where the generation code went wrong.
CREATE OR REPLACE FUNCTION test()
RETURNS varchar
AS
$BODY$
DECLARE
l_source_table text;
l_backup_table text;
l_sql text;
BEGIN
l_source_table := 'table_name';
l_backup_table := l_source_table||'_'||to_char(current_date, 'ddmmyyyy')||'_1';
l_sql := format('create table %I as select * from %I', l_backup_table, l_source_table);
-- for debugging purposes:
raise notice 'Running: %', l_sql
EXECUTE l_sql;
RETURN 'Y';
EXCEPTION
WHEN others THEN RETURN 'N';
END;
$BODY$
LANGUAGE plpgsql;
Note that I also used variables for the source and backup table to be able to use that as a place holder for the format() function.
Online example
I'm having problems executing a "perform create index" inside of a plgpsql function (postgres 9.4). For example:
create or replace function foo() returns void language plpgsql as $$
begin
perform 'create unique index patients_row_id_key on patients(row_id)';
end; $$;
It seems to run fine:
select foo();
However, the index is not created. Any diagnosis and workaround? I tried:
alter function foo() VOLATILE;
and still no luck.
What #Abelisto wrote about PERFORM.
And what #Chris added about SQL injection.
Plus, I suggest to use format() for anything except the most trivial query strings to make your life with dynamic SQL easier. And the manual does, too:
A cleaner approach is to use format()'s %I specification for table or column names.
CREATE OR REPLACE FUNCTION foo(_tbl text)
RETURNS void AS
$func$
BEGIN
EXECUTE format('CREATE UNIQUE INDEX %I ON %I(row_id)', _tbl || _row_id_key', _tbl);
END
$func$ LANGUAGE plpgsql;
A regclass parameter is a convenient alternative for passing table names, but concatenating new identifiers can be tricky - as this recent related case goes to show:
PL/pgSQL regclass quoting of table named like keyword
As a supplement to the point of using execute, note two important points about this.
You are doing string interpolation with sql queries (dangerous!), and
You have to use quote_ident, not quote_literal
If you use Abelisto's function above, and call it with:
SELECT foo('test_idx on test; drop table foo; --');
SQL injection in stored procedure. Worse if it is security definer. A fixed version would be:
create or replace function foo(p_tablename text) returns void language plpgsql as $$
begin
execute 'create unique index ' || quote_ident(p_tablename || '_row_id_key') || ' on ' || quote_ident(p_tablename) || '(row_id)';
end; $$;
PERFORM statement in the PLPGSQL used to execute queries which does not return result or which result is not useful. Technically PERFORM ... inside the PLPGSQL block is equal to SELECT ... in the plain SQL. So in your example you are trying to execute something like
select 'create unique index patients_row_id_key on patients(row_id)';
and just ignore the result.
Read more: Executing a Command With No Result
You should not to wrap DDL statements inside PLPGSQL and can use it as is:
create or replace function foo() returns void language plpgsql as $$
begin
create unique index patients_row_id_key on patients(row_id);
end; $$;
Or if you want to construct it at runtime then use EXECUTE statement: Executing Dynamic Commands like this:
create or replace function foo(p_tablename text) returns void language plpgsql as $$
begin
execute 'create unique index ' || p_tablename || '_row_id_key on ' || p_tablename || '(row_id)';
end; $$;
I have created the following function to truncate bunch of tables starting with "irm_gtresult". There are no syntax errors in my function, but the function doesn't truncate the tables when I run it. What could be wrong here?
My Postgres db version is 8.4.
create or replace function br()
RETURNS void
LANGUAGE plpgsql
AS
$$
DECLARE
row text;
BEGIN
FOR row IN
select table_name from information_schema.tables where table_name ILIKE 'irm_gtresult%'
LOOP
EXECUTE 'TRUNCATE TABLE ' || row;
END LOOP;
END;
$$;
Call:
select br();
Your code is valid. I tested and it works for me in Postgres 9.4.
Using the outdated and unsupported version 8.4 (like you added) may be the problem. The version is just too old, consider upgrading to a current version.
However, I have a couple of suggestions:
Don't use key word row as variable name.
You don't need to loop, you can TRUNCATE all tables in a single command. Faster, shorter.
You may need to add CASCADE if there are dependencies. Be aware of the effect.
CREATE OR REPLACE FUNCTION br()
RETURNS void AS
$func$
BEGIN
EXECUTE (
SELECT 'TRUNCATE TABLE '
|| string_agg(format('%I.%I', schemaname, tablename), ',')
|| ' CASCADE'
FROM pg_tables t
WHERE tablename ILIKE 'irm_gtresult%'
AND schemaname = 'public'
-- AND tableowner = 'postgres' -- optionaly restrict to one user
);
END
$func$ LANGUAGE plpgsql;
Call:
SELECT br();
I am using the view pg_tables from the system catalog. You can as well use information_schema.tables like you did. Note the subtle differences:
How to check if a table exists in a given schema
Related answers with more explanation:
Can I truncate tables dynamically?
Truncating all tables in a Postgres database
To truncate in postgres you just have to use the TRUNC() function.
Example:
SELECT TRUNC(price, 0) AS truncated_price
FROM product;
Let's say I have a function show_files(IN file text, IN suffix text, OUT statement text). In next step the function is called:
SELECT * FROM show_files(file := 'example', suffix := '.png');
My question is: Is there any solution that I could get statement that has called this function from inside that function?
I mean, after running the SELECT the output of function (OUT statement text) should be: 'SELECT * FROM show_files(file := 'example', suffix := '.png');', or is it possible to assign this statement to the variable inside the function?
I need the functionality like those with TG_NAME, TG_OP, etc. in trigger procedures.
Maybe is it possible to retrieve this statement from SELECT current_query FROM pg_stat_activity ?
When I'm trying to use it inside a function I've got an empty record:
CREATE OR REPLACE FUNCTION f_snitch(text)
RETURNS text AS
$BODY$
declare
rr text;
BEGIN
RAISE NOTICE '.. from f_snitch.';
-- do stuff
SELECT current_query into rr FROM pg_stat_activity
WHERE current_query ilike 'f_snitch';
RETURN rr;
END
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
Any help and suggestions would be happily welcome!
TG_NAME and friends are special variables that only exist for trigger functions. Regular plpgsql functions don't have anything like that. I am fresh out of ideas how you could possibly get this inside the called function in plpgsql.
You could add RAISE NOTICE to your function so you get the desired information
CREATE OR REPLACE FUNCTION f_snitch(text)
RETURNS text LANGUAGE plpgsql AS
$func$
BEGIN
RAISE NOTICE '.. from f_snitch.';
-- do stuff
RETURN 'Snitch says hi!';
END
$func$;
Call:
SELECT f_snitch('foo')
In addition to the result, this returns a notice:
NOTICE: .. from f_snitch.
Fails to please in two respects:
Calling statement is not in the notice.
No CONTEXT in the notice.
For 1. you can use RAISE LOG instead (or set your cluster up to log NOTICES, too - which I usually don't, too verbose for me). With standard settings, you get an additional line with the STATEMENT in the database log:
LOG: .. from f_snitch.
STATEMENT: SELECT f_snitch('foo')
For 2., have a look at this related question at dba.SE. CONTEXT would look like:
CONTEXT: SQL statement "SELECT f_raise('LOG', 'My message')"
PL/pgSQL function "f_snitch" line 5 at PERFORM
Ok, I've got it!
CREATE OR REPLACE FUNCTION f_snitch(text)
RETURNS setof record AS
$BODY$
BEGIN
RETURN QUERY
SELECT current_query
FROM pg_stat_activity
<strike>ORDER BY length(current_query) DESC LIMIT 1;</strike>
where current_query ilike 'select * from f_snitch%';
-- much more reliable solution
END
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
select * from f_snitch('koper') AS (tt text);
And here is the result:
It's probably not 100% reliable solution but for small systems (for few users) it's quite ok.
I would like to write "procedures" in DB2 9.7 without defining the "CREATE PROCEDURE" -statement. Apparently this is something called "compiled" sql statement. However, I am having problems in getting valid syntax. E.g. the syntax below does not seem to work:
BEGIN
DECLARE V_SQL VARCHAR(1024);
SET V_SQL = 'BEGIN
IF EXISTS(SELECT NAME FROM SYSIBM.SYSTRIGGERS WHERE NAME = ''TRIGGER_EMPLOYEE_FOR_DELETES'') THEN
DROP TRIGGER TRIGGER_EMPLOYEE_FOR_DELETES;
END IF;
END;';
PREPARE S1 FROM V_SQL;
EXECUTE S1;
END
I have tried adding/removing ";" and statement symbol "!" but still cannot get it to work.
You cannot have a DROP TRIGGER statement within a compound SQL statement. See the DB2 documentation for compound SQL.
If you are able to move the IF statement outside of V_SQL, you could do something like this:
BEGIN
DECLARE V_SQL VARCHAR(1024);
IF EXISTS(SELECT NAME FROM SYSIBM.SYSTRIGGERS
WHERE NAME = 'TRIGGER_EMPLOYEE_FOR_DELETES'
) THEN
SET V_SQL = 'DROP TRIGGER TRIGGER_EMPLOYEE_FOR_DELETES;';
PREPARE S1 FROM V_SQL;
EXECUTE S1;
END IF;
END
Of course, this wouldn't work if you need to set your condition dynamically.