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
Related
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?
I'm trying to store a simple SELECT query with the new CREATE PROCEDURE method in PostgreSQL 11. My idea is to store the queries in the DB, because I can have a much simple code in my API server and maybe I don't need to develop a query builder if I can use if/else in an sql function with enforced type safety. I have this minimal example:
First I tried this plpgsql function:
CREATE OR REPLACE PROCEDURE test_proc() AS $$
BEGIN
SELECT * FROM my_db
LIMIT 1;
END;
$$ LANGUAGE plpgsql;
CALL test_proc();
However throws this error:
ERROR: query has no destination for result data
HINT: If you want to discard the results of a SELECT, use PERFORM instead.
CONTEXT: PL/pgSQL function test_proc() line 3 at SQL statement SQL state: 42601
If I trying to use RETURN QUERY:
CREATE OR REPLACE PROCEDURE test_proc() AS $$
BEGIN
RETURN QUERY;
SELECT * FROM my_db
LIMIT 1;
END;
$$ LANGUAGE plpgsql;
I'm getting this error:
ERROR: cannot use RETURN QUERY in a non-SETOF function
LINE 17: RETURN QUERY; ^
SQL state: 42804
Character: 310
I'm also getting error when I try to use RETURNS void AS $$ or RETURNS table(...) AS $$. Seems like RETURNS not supported in CREATE PROCEDURE? So, is it possible to return a table with the new stored procedure method? Or if it's not, maybe JSON?
Procedures in PostgreSQL (Oracle, DB2) are not same like procedures in MS-SQL. It has different target, and you cannot use it. Usually, the best what you can do, forgot all what you know from MSSQL. The procedural part is really different.
Only functions can returns some data - so you need to use functions. Functions can returns scalar value, composite value or array value, or table. You want function that returns table.
CREATE OR REPLACE FUNCTION fx()
RETURNS SETOF mytab AS $$
BEGIN
RETURN QUERY SELECT * FROM mytab;
END
$$ LANGUAGE plpgsql;
SELECT * FROM fx();
For record:
You can use SQL function, that can have better (or worse) performance (depends on context). These functions are sometimes named as parametrized views.
CREATE OR REPLACE FUNCTION fx()
RETURNS SETOF mytab AS $$
SELECT * FROM mytab;
$$ LANGUAGE sql;
Attention: this technique is antipattern!!! Don't do it. It is really not good idea. The functions should not to wrap queries. If you want to hide some complexity of queries, then use a views. Don't use a functions. Functions are effective barier for query optimizer, and when you use this antipattern, then optimizer cannot to well optimize any non trivial queries that use in this form evaluated subqueries.
Use it - if you want very very slow applications - or if your data model or queries are primitive. In other cases, don't do it.
Don't afraid of SQL - it is great language designed for manual usage. It is good to place all data access to one module (model), to don't access database everywhere in your code, but it is bad too hide SQL in your code.
First of all Procedure was introduced in PostgreSQL 11, If you are using below 11th version, you cannot use Procedures. Instead to Procedure you can use functions.
Syntax to create function
CREATE or replace function function_name(_parameter varchar)
returns table(col1 varchar, col2 varchar, col3 varchar)
language 'plpgsql'
as $BODY$
BEGIN
return query select a.col1, a.col2, b.col3 from table a
join table2 as b on a.col1 = b.col1;
END;
$BODY$;
you can call a function same a like table
select * From function_name('sample data');
syntax to create Procedure.
CREATE OR REPLACE PROCEDURE procedure_name(_parameter varcar,INOUT result refcursor)
LANGUAGE 'plpgsql'
AS $BODY$
BEGIN
open result for SELECT , * from sampletable where a = _parameter;
END;
$BODY$;
you can execute a Procedure using call keyword, within a transaction
BEGIN;
CALL public.procedure_name( 'sample data', 'test');
fetch all in "test";
COMMIT;
The postgreSql 11. we have to create a stored procedure
there is the solution :
Create procedure to execute query in PostgreSQL
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 $$
begin
execute 'create unique index ' || p_tablename || '_row_id_key on ' || p_tablename || '(row_id)';
end; $$;
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.
While executing below shown trigger code using ANT I am getting the error
org.postgresql.util.PSQLException: ERROR: unterminated quoted string at or near "' DECLARE timeout integer"
Position: 57
I am able to sucessfully execute the below code through PGADmin (Provided by postgres) and command line utility "psql" and the trigger function is added but while executing through ANT it fails everytime
BEGIN TRANSACTION;
CREATE OR REPLACE FUNCTION sweeper() RETURNS trigger as '
DECLARE
timeout integer;
BEGIN
timeout = 30 * 24 * 60 * 60 ;
DELETE FROM diagnosticdata WHERE current_timestamp - teststarttime > (timeout * ''1 sec''::interval);
return NEW;
END;
' LANGUAGE 'plpgsql';
-- Trigger: sweep on diagnosticdata
CREATE TRIGGER sweep
AFTER INSERT
ON diagnosticdata
FOR EACH ROW
EXECUTE PROCEDURE sweeper();
END;
I encountered this error in liquibase and this page was one of the first search results so I guess I share my solution at this page:
You can put your whole sql in a separate file and include this in the changeset.
Its important to set the splitStatements option to false.
The whole changeset would then look like
<changeSet author="fgrosse" id="530b61fec3ac9">
<sqlFile path="your_sql_file_here.sql" splitStatements="false"/>
</changeSet>
I always like to have those big SQL parts (like function updates and such) in separate files.
This way you get proper syntax highlighting when opening the sql file and dont have to intermix XML and SQL in one file.
Edit: as mentioned in the comments its worth noting that the sql change supports the splitStatements option as well (thx to AndreyT for pointing that out).
I had the same problem with the JDBC driver used by Liquibase.
It seems that the driver explodes each line ended by a semicolon and runs it as a separate SQL command. That is why the code below will be executed by the JDBC driver in the following sequence:
CREATE OR REPLACE FUNCTION test(text) RETURNS VOID AS ' DECLARE tmp text
BEGIN tmp := "test"
END;
' LANGUAGE plpgsql
Of course, this is invalid SQL and causes the following error:
unterminated dollar-quoted string at or near ' DECLARE tmp text
To correct this, you need to use backslashes after each line ended with semicolon:
CREATE OR REPLACE FUNCTION test(text)
RETURNS void AS ' DECLARE tmp text; \
BEGIN
tmp := "test"; \
END;' LANGUAGE plpgsql;
Alternatively, you can place the whole definition in one line.
I am using HeidiSQL client and this was solved by placing DELIMITER // before CREATE OR REPLACE statement. There is a also a 'Send batch in one go' option in HeidiSQL that essentially achieves the same thing.
This error arises as an interaction between the particular client used to connect to the server and the form of the function. To illustrate:
The following code will run without casualty in Netbeans 7, Squirrel, DbSchema, PgAdmin3
CREATE OR REPLACE FUNCTION author.revision_number()
RETURNS trigger AS
$BODY$
begin
new.rev := new.rev + 1;
new.revised := current_timestamp;
return new;
end;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
Please note that the 'begin' statement comes immediately after the '$' quoted string.
The next code will halt all the above clients except PgAdmin3.
CREATE OR REPLACE FUNCTION author.word_count()
RETURNS trigger AS
$BODY$
declare
wordcount integer := 0; -- counter for words
indexer integer := 1; -- position in the whole string
charac char(1); -- the first character of the word
prevcharac char(1);
begin
while indexer <= length(new.blab) loop
charac := substring(new.blab,indexer,1); -- first character of string
if indexer = 1 then
prevcharac := ' '; -- absolute start of counting
else
prevcharac := substring(new.blab, indexer - 1, 1); -- indexer has increased
end if;
if prevcharac = ' ' and charac != ' ' then
wordcount := wordcount + 1;
end if;
indexer := indexer + 1;
end loop;
new.words := wordcount;
return new;
end;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
The crucial difference in the second example is the 'declare' section. The ploy of using back-slashes raises an error with PgAdmin3.
In summary I suggest trying different tools. Some tools even though they are supposed to be writing text files put invisible stuff into the text. Notoriously this occurs with the Unicode BOM which will halt any php file that tries to implement sessions or namespaces.
Whilst this is no solution I hope it helps.
I had the same problem with zeos and c++ builder.
The solution in my case:
Change the property delimiter (usually ";") to another in the component (class) I used.
dm->ZSQLProcessor1->DelimiterType=sdGo;
Perhaps Ant have something similar.
I know this question was asked a long time ago but I had kind of the same issue with a Postgresql script (run from Jenkins) using Ant's SQL Task.
I tried to run this SQL (saved in a file named audit.sql):
DROP SCHEMA IF EXISTS audit CASCADE
;
CREATE SCHEMA IF NOT EXISTS audit AUTHORIZATION faktum
;
CREATE FUNCTION audit.extract_interval_trigger ()
RETURNS trigger AS $extractintervaltrigger$
BEGIN
NEW."last_change_ts" := current_timestamp;
NEW."last_change_by" := current_user;
RETURN NEW;
END;
$extractintervaltrigger$ LANGUAGE plpgsql
;
but got the error "unterminated dollar-quoted string". No problem running it from pgAdmin.
I found out that it is not the driver that split the script at every ";" but rather Ant.
At http://grokbase.com/t/postgresql/pgsql-jdbc/06cjx3s3y0/ant-sql-tag-for-dollar-quoting I found the answer:
Ant eats double-$$ as part of its variable processing. You have to use
$BODY$ (or similar) in the stored procs, and put the delimiter on its
own line (with delimitertype="row"). Ant will cooperate then.
My Ant SQL script looks like this and it works:
<sql
driver="org.postgresql.Driver" url="jdbc:postgresql://localhost:5432/jenkins"
userid="user" password="*****"
keepformat="true"
autocommit="true"
delimitertype="row"
encoding="utf-8"
src="audit.sql"
/>
This example worked for me with PostgreSQL 14.1 and HeidiSQL 9.4.0.5125
DROP TABLE IF EXISTS emp;
CREATE TABLE emp (
empname text NOT NULL,
salary integer
);
DROP TABLE IF EXISTS EMP_AUDIT;
CREATE TABLE emp_audit(
operation char(1) NOT NULL,
stamp timestamp NOT NULL,
userid text NOT NULL,
empname text NOT NULL,
salary integer
);
DELIMITER //
CREATE OR REPLACE FUNCTION process_emp_audit() RETURNS TRIGGER AS $$
BEGIN
--
-- Create a row in emp_audit to reflect the operation performed on emp,
-- make use of the special variable TG_OP to work out the operation.
--
IF (TG_OP = 'DELETE') THEN
INSERT INTO emp_audit SELECT 'D', now(), user, OLD.*;
RETURN OLD;
ELSIF (TG_OP = 'UPDATE') THEN
INSERT INTO emp_audit SELECT 'U', now(), user, NEW.*;
RETURN NEW;
ELSIF (TG_OP = 'INSERT') THEN
INSERT INTO emp_audit SELECT 'I', now(), user, NEW.*;
RETURN NEW;
END IF;
RETURN NULL; -- result is ignored since this is an AFTER trigger
END;
$$ LANGUAGE plpgsql;
DROP TRIGGER IF EXISTS emp_audit ON emp;
CREATE TRIGGER emp_audit
AFTER INSERT OR UPDATE OR DELETE ON emp
FOR EACH ROW EXECUTE PROCEDURE process_emp_audit();
I was receiving the same error because I had my semicolon in a new line like this:
WHERE colA is NULL
;
Make sure they are in a single line as
WHERE colA is NULL;