Related
Hi every one I have multiple spatial tables That I want to control, so that I created a table where I will store the name of the operation applied on my layers tables(insert,update or delete), operation time and the team who did it, number of spatial tables created.
My script table
CREATE TABLE public.monitoring_table
(
operation character(1) COLLATE pg_catalog."default",
operat_ime timestamp without time zone,
userid text COLLATE pg_catalog."default",
dc_team text COLLATE pg_catalog."default",
number_pts_created integer,
id integer NOT NULL DEFAULT nextval('monitoring_table_id_seq'::regclass),
CONSTRAINT monitoring_table_pkey PRIMARY KEY (id)
)
WITH (
OIDS = FALSE
)
TABLESPACE pg_default;
ALTER TABLE public.monitoring_table
OWNER to postgres;
after that I stored all the teams that I have on my table :
insert into monitoring_table (dc_team) values ('abdoulhassan');
insert into monitoring_table (dc_team) values ('abdoulei');
insert into monitoring_table (dc_team) values ('danis');
insert into monitoring_table (dc_team) values ('david');
insert into monitoring_table (dc_team) values ('joseph');
To calculate the number of spatial tables created, I executed this function :
My counting function :
DROP FUNCTION get_dc_team_counting();
CREATE OR REPLACE FUNCTION get_dc_team_counting()
RETURNS bigint AS
$func$
DECLARE
dc_team text;
_tbl_pattern text;
_schema text = 'sige';
_tb_name information_schema.tables.table_name%TYPE;
_tc bigint;
BEGIN
FOR _tb_name IN
SELECT table_name
FROM information_schema.tables
WHERE table_schema = _schema
AND table_name ~ _tbl_pattern
LOOP
EXECUTE format('SELECT count(*) FROM %I.%I where id= 583', _schema, _tb_name)
INTO _tc;
return _tc;
END LOOP;
END
$func$ LANGUAGE plpgsql
To get the team I executed this function :
CREATE OR REPLACE FUNCTION get_team()
RETURNS text AS -- or whatever you want to return
$func$
DECLARE
dc_team text;
_tbl_pattern text;
_schema text = 'public';
_tb_name information_schema.tables.table_name%TYPE; -- currently varchar
_tc text;
BEGIN
FOR _tb_name IN
SELECT table_name
FROM information_schema.tables
WHERE table_schema = _schema
AND table_name ~ _tbl_pattern -- see below!
LOOP
EXECUTE format('SELECT dc_team FROM %I.%I where id = 26', _schema, _tb_name)
INTO _tc;
return _tc;
END LOOP;
END
$func$ LANGUAGE plpgsql;
In my where clause I want to get dynamically the value of the ID. I don't want to give it manually in the function. I don't see how to do it.
Now I created a trigger function to be able to update my table if a row was inserted, updated or deleted. I did it this way :
CREATE OR REPLACE FUNCTION process_monitoring() RETURNS TRIGGER AS $monitoring$
BEGIN
IF (TG_OP = 'DELETE') THEN
update monitoring_table set operation = 'D', operat_ime = now(), userid = user ,dc_team = OLD.dc_team, number_pts_created = get_dc_team_counting() where dc_team = get_team();
RETURN OLD;
ELSIF (TG_OP = 'UPDATE') THEN
update monitoring_table set operation = 'U',operat_ime = now(),userid = user , dc_team = NEW.dc_team, number_pts_created = get_dc_team_counting() where dc_team = get_team();
RETURN NEW;
ELSIF (TG_OP = 'INSERT') THEN
update monitoring_table set operation = 'I', operat_ime = now(), userid = user, dc_team = NEW.dc_team, number_pts_created = get_dc_team_counting() where dc_team = get_team();
RETURN NEW;
END IF;
RETURN NULL;
END;
$monitoring$ LANGUAGE plpgsql;
CREATE TRIGGER monitoring
AFTER INSERT OR UPDATE OR DELETE ON sige.valve
FOR EACH ROW EXECUTE PROCEDURE process_monitoring();
In my previous functions I used known values of ids in the where clauses, but when I try to insert or update a value on the concerned table I get this error :
the control attempted it's end without return
CONTEXT: fonction PL/pgsql get_team()
instruction SQL « update monitoring_table set operation = 'U',operat_ime = now(),userid = user , dc_team = NEW.dc_team, number_pts_created = get_dc_team_counting() where dc_team = get_team() »
fonction PL/pgsql process_monitoring(), ligne 10 à instruction SQL
If you have any idea about the origin of the error and how to get dynamically a value of a field and put it in the where clause tell me please.
I'm a newbie and I'm struggling, any assistance would be warmly appreciated.
I'm using PostgreSQL.
I have the following small MVWE for a basic micro-auditing system which works fine but lacks a functionality:
DROP TABLE IF EXISTS audit CASCADE;
CREATE TABLE audit(
Id BIGSERIAL NOT NULL
,TimeValue TIMESTAMP NOT NULL
,RoleName NAME NOT NULL
,Operation NAME NOT NULL
,SchemaName NAME NOT NULL
,TableName NAME NOT NULL
,Identifiers BIGINT[]
---
,PRIMARY KEY(Id)
);
-- Audit Trigger:
DROP FUNCTION IF EXISTS audit_trigger() CASCADE;
CREATE OR REPLACE FUNCTION audit_trigger()
RETURNS TRIGGER AS
$BODY$
BEGIN
INSERT INTO audit(TimeValue, RoleName, Operation, SchemaName, TableName) VALUES
(now()::TIMESTAMP, current_user, TG_OP, TG_TABLE_SCHEMA, TG_RELNAME);
RETURN NULL;
END;
$BODY$
LANGUAGE plpgsql SECURITY DEFINER;
-- Channels:
DROP TABLE IF EXISTS channels CASCADE;
CREATE TABLE channels(
Id INTEGER NOT NULL
,UserKey TEXT NOT NULL
,Active BOOLEAN NOT NULL DEFAULT(TRUE)
---
,PRIMARY KEY(Id)
,UNIQUE(UserKey)
);
CREATE TRIGGER channel_audit_trigger BEFORE INSERT OR UPDATE OR DELETE ON channels
FOR EACH STATEMENT EXECUTE PROCEDURE audit_trigger();
-- Perform some operations:
INSERT INTO channels(
SELECT C.Id, 'Channel-' || C.Id
FROM generate_series(1, 300, 10) AS C(Id)
);
DELETE FROM channels WHERE id < 10;
UPDATE channels
SET UserKey = 'wild channel'
WHERE id = 21;
I would like to add into the last column of audit table, identifiers of rows that have been inserted/updated/deleted in channels.
I have used STATEMENT level because I just need to collects identifiers in a array. But I do not find how to access DML statistics. Conversely at the ROW level I must handle OLD and NEW cases and I cannot succeed in aggregate all touched identifier.
How can I proceed in order to fill the last column of audit table with touched identifiers?
Update
Finally I reached my goal, but this solution might not be scalable and may have some unwanted drawbacks (I am open to any constructive feedback and advice).
Basically, how I have solved my problem:
Log at ROW level BEFORE DML is performed into a table audit_rowlevel;
Aggregate the freshly added content of audit_rowlevel into audit_statementlevel at STATEMENT level AFTER DML is performed;
Minimal Working Example is now:
DROP TABLE IF EXISTS audit_rowlevel CASCADE;
CREATE TABLE audit_rowlevel(
Id BIGSERIAL NOT NULL
,Aggregated BOOLEAN NOT NULL DEFAULT(FALSE)
,TimeValue TIMESTAMP NOT NULL
-- https://www.postgresql.org/docs/current/static/functions-info.html
,RoleName NAME NOT NULL
,ClientIP INET NOT NULL
,ClientPid INTEGER NOT NULL
-- https://www.postgresql.org/docs/current/static/plpgsql-trigger.html
,Operation TEXT NOT NULL
,SchemaName NAME NOT NULL
,TableName NAME NOT NULL
,RowId BIGINT NOT NULL
-- https://www.postgresql.org/docs/current/static/functions-json.html
,OldValue JSONB
,NewValue JSONB
---
,PRIMARY KEY(Id)
);
-- Row Level Trigger:
DROP FUNCTION IF EXISTS audit_rowlevel_trigger() CASCADE;
CREATE OR REPLACE FUNCTION audit_rowlevel_trigger()
RETURNS TRIGGER AS
$BODY$
DECLARE
history BOOLEAN := (TG_NARGS > 0) AND (TG_ARGV[0]::BOOLEAN);
rowid BIGINT;
oldvalue JSONB;
newvalue JSONB;
BEGIN
-- Handle NEW:
IF TG_OP = ANY('{INSERT,UPDATE}') THEN
IF history THEN
newvalue := to_jsonb(NEW);
END IF;
rowid := NEW.Id::BIGINT;
END IF;
-- Handle OLD:
IF TG_OP = ANY('{UPDATE,DELETE}') THEN
IF history THEN
oldvalue := to_jsonb(OLD);
END IF;
rowid := OLD.Id::BIGINT;
END IF;
-- INSERT:
INSERT INTO audit_rowlevel(TimeValue, RoleName, ClientIP, ClientPID, Operation, SchemaName, TableName, RowId, NewValue, OldValue) VALUES
(now()::TIMESTAMP, current_user, inet_client_addr(), pg_backend_pid(), TG_OP, TG_TABLE_SCHEMA, TG_RELNAME, RowId, NewValue, OldValue);
-- RETURN:
IF TG_OP = ANY('{INSERT,UPDATE}') THEN
RETURN NEW;
ELSIF TG_OP = 'DELETE' THEN
RETURN OLD;
ELSE
RETURN NULL;
END IF;
END;
$BODY$
LANGUAGE plpgsql SECURITY DEFINER;
-- Statement Level Trigger:
DROP TABLE IF EXISTS audit_statementlevel CASCADE;
CREATE TABLE audit_statementlevel(
Id BIGSERIAL NOT NULL
,TimeValue TIMESTAMP NOT NULL
,RoleName NAME NOT NULL
,ClientIP INET NOT NULL
,ClientPid INTEGER NOT NULL
,Operation TEXT NOT NULL
,SchemaName NAME NOT NULL
,TableName NAME NOT NULL
,RowCount BIGINT NOT NULL
,RowIds BIGINT[] NOT NULL
,AuditIds BIGINT[] NOT NULL
---
,PRIMARY KEY(Id)
);
-- Row Level Trigger:
DROP FUNCTION IF EXISTS audit_statementlevel_trigger() CASCADE;
CREATE OR REPLACE FUNCTION audit_statementlevel_trigger()
RETURNS TRIGGER AS
$BODY$
DECLARE
rowcount BIGINT;
BEGIN
WITH
A AS (
SELECT
TimeValue, RoleName, ClientIP, ClientPid, Operation, SchemaName, TableName
,COUNT(*)
,array_agg(RowId)
,array_agg(Id)
FROM
audit_rowlevel
WHERE
NOT Aggregated
GROUP BY
TimeValue, RoleName, ClientIP, ClientPid, Operation, SchemaName, TableName
ORDER BY
TimeValue
),
B AS (
INSERT INTO audit_statementlevel(TimeValue, RoleName, ClientIP, ClientPid, Operation, SchemaName, TableName, RowCount, RowIds, AuditIds)
(SELECT * FROM A)
RETURNING AuditIds
),
C AS (
SELECT array_agg(DISTINCT T.id) AS Ids FROM B, unnest(B.AuditIds) AS T(id)
)
UPDATE
audit_rowlevel
SET
Aggregated = TRUE
FROM
C
WHERE
Id = ANY(C.Ids);
RETURN NULL;
END;
$BODY$
LANGUAGE plpgsql SECURITY DEFINER;
-- Channels:
DROP TABLE IF EXISTS channels CASCADE;
CREATE TABLE channels(
Id INTEGER NOT NULL
,UserKey TEXT NOT NULL
,Active BOOLEAN NOT NULL DEFAULT(TRUE)
---
,PRIMARY KEY(Id)
,UNIQUE(UserKey)
);
CREATE TRIGGER channel_audit_rowlevel_trigger BEFORE INSERT OR UPDATE OR DELETE ON channels
FOR EACH ROW EXECUTE PROCEDURE audit_rowlevel_trigger(TRUE);
CREATE TRIGGER channel_audit_statementlevel_trigger AFTER INSERT OR UPDATE OR DELETE ON channels
FOR EACH STATEMENT EXECUTE PROCEDURE audit_statementlevel_trigger();
-- Perform some operations:
INSERT INTO channels(
SELECT C.Id, 'Channel-' || C.Id
FROM generate_series(1, 300, 10) AS C(Id)
);
DELETE FROM channels WHERE id < 10;
UPDATE channels
SET UserKey = 'wild channel'
WHERE id = 21;
I am interested knowing if this solution looks right to professional developers.
Am I going into the good direction or is this solution evil?
I have a function (audit.create_audit_table()) that accepts an array of table names. It creates a single function audit.if_modified_func() and then loops through each table name and creates an audit table and applies a trigger to the main table. The function compiles and is created with no errors. When I run the function
select audit.create_audit_table(ARRAY['organization'])
I keep getting the following error and I am not sure why because I thought that TG_TABLE_NAME is a automatic variable which will give me access to the current table that is executing audit.if_modified_func()
ERROR:
ERROR: column "tg_table_name" does not exist
LINE 3: audit_row audit.' || quote_ident(TG_TABLE_NAME::TEXT)||';
^
Here's the function:
CREATE OR REPLACE FUNCTION audit.create_audit_table(table_names character varying[])
RETURNS character varying AS
$BODY$
DECLARE
table_name varchar;
i int;
BEGIN
EXECUTE 'CREATE OR REPLACE FUNCTION audit.if_modified_func() RETURNS TRIGGER AS $$
DECLARE
audit_row audit.' || quote_ident(TG_TABLE_NAME::TEXT)||';
include_values boolean;
log_diffs boolean;
h_old hstore;
h_new hstore;
excluded_cols text[] = ARRAY[]::text[];
BEGIN
IF TG_WHEN <> ''AFTER'' THEN
RAISE EXCEPTION ''audit.if_modified_func() may only run as an AFTER trigger'';
END IF;
audit_row = ROW(
nextval(''audit.'|| quote_ident(TG_TABLE_NAME::text) ||'_event_id_seq''), -- event_id
TG_TABLE_SCHEMA::text, -- schema_name
TG_TABLE_NAME::text, -- table_name
TG_RELID, -- relation OID for much quicker searches
session_user::text, -- session_user_name
current_timestamp, -- action_tstamp_tx
statement_timestamp(), -- action_tstamp_stm
clock_timestamp(), -- action_tstamp_clk
txid_current(), -- transaction ID
current_setting(''application_name''), -- client application
inet_client_addr(), -- client_addr
inet_client_port(), -- client_port
current_query(), -- top-level query or queries (if multistatement) from client
substring(TG_OP,1,1), -- action
NULL, NULL, -- row_data, changed_fields
''f'' -- statement_only
);
IF NOT TG_ARGV[0]::boolean IS DISTINCT FROM ''f''::boolean THEN
audit_row.client_query = NULL;
END IF;
IF TG_ARGV[1] IS NOT NULL THEN
excluded_cols = TG_ARGV[1]::text[];
END IF;
IF (TG_OP = ''UPDATE'' AND TG_LEVEL = ''ROW'') THEN
audit_row.row_data = hstore(OLD.*) - excluded_cols;
audit_row.changed_fields = (hstore(NEW.*) - audit_row.row_data) - excluded_cols;
IF audit_row.changed_fields = hstore('''') THEN
-- All changed fields are ignored. Skip this update.
RETURN NULL;
END IF;
ELSIF (TG_OP = ''DELETE'' AND TG_LEVEL = ''ROW'') THEN
audit_row.row_data = hstore(OLD.*) - excluded_cols;
ELSIF (TG_OP = ''INSERT'' AND TG_LEVEL = ''ROW'') THEN
audit_row.row_data = hstore(NEW.*) - excluded_cols;
ELSIF (TG_LEVEL = ''STATEMENT'' AND TG_OP IN (''INSERT'',''UPDATE'',''DELETE'',''TRUNCATE'')) THEN
audit_row.statement_only = ''t'';
ELSE
RAISE EXCEPTION ''[audit.if_modified_func] - Trigger func added as trigger for unhandled case: %%, %%'',TG_OP, TG_LEVEL;
RETURN NULL;
END IF;
INSERT INTO audit.'|| quote_ident(TG_TABLE_NAME::TEXT) ||' VALUES (audit_row.*);
RETURN null;
END;
$$
LANGUAGE plpgsql;
ALTER FUNCTION audit.if_modified_func()
OWNER TO postgres;';
FOR i in 1..array_upper(table_names, 1) LOOP
EXECUTE format('
DROP TABLE IF EXISTS audit.%1$s;
CREATE TABLE audit.%1$s (
event_id bigserial primary key,
schema_name text not null,
table_name text not null,
relid oid not null,
session_user_name text,
action_tstamp_tx TIMESTAMP WITH TIME ZONE NOT NULL,
action_tstamp_stm TIMESTAMP WITH TIME ZONE NOT NULL,
action_tstamp_clk TIMESTAMP WITH TIME ZONE NOT NULL,
transaction_id bigint,
application_name text,
client_addr inet,
client_port integer,
client_query text,
action TEXT NOT NULL CHECK (action IN (''I'',''D'',''U'', ''T'')),
row_data hstore,
changed_fields hstore,
statement_only boolean not null
);
REVOKE ALL ON audit.%1$s FROM public;
COMMENT ON TABLE audit.%1$s IS ''History of auditable actions on audited tables, from audit.if_modified_func()'';
COMMENT ON COLUMN audit.%1$s.event_id IS ''Unique identifier for each auditable event'';
COMMENT ON COLUMN audit.%1$s.schema_name IS ''Database schema audited table for this event is in'';
COMMENT ON COLUMN audit.%1$s.table_name IS ''Non-schema-qualified table name of table event occured in'';
COMMENT ON COLUMN audit.%1$s.relid IS ''Table OID. Changes with drop/create. Get with ''''tablename''''::regclass'';
COMMENT ON COLUMN audit.%1$s.session_user_name IS ''Login / session user whose statement caused the audited event'';
COMMENT ON COLUMN audit.%1$s.action_tstamp_tx IS ''Transaction start timestamp for tx in which audited event occurred'';
COMMENT ON COLUMN audit.%1$s.action_tstamp_stm IS ''Statement start timestamp for tx in which audited event occurred'';
COMMENT ON COLUMN audit.%1$s.action_tstamp_clk IS ''Wall clock time at which audited event''''s trigger call occurred'';
COMMENT ON COLUMN audit.%1$s.transaction_id IS ''Identifier of transaction that made the change. May wrap, but unique paired with action_tstamp_tx.'';
COMMENT ON COLUMN audit.%1$s.client_addr IS ''IP address of client that issued query. Null for unix domain socket.'';
COMMENT ON COLUMN audit.%1$s.client_port IS ''Remote peer IP port address of client that issued query. Undefined for unix socket.'';
COMMENT ON COLUMN audit.%1$s.client_query IS ''Top-level query that caused this auditable event. May be more than one statement.'';
COMMENT ON COLUMN audit.%1$s.application_name IS ''Application name set when this audit event occurred. Can be changed in-session by client.'';
COMMENT ON COLUMN audit.%1$s.action IS ''Action type; I = insert, D = delete, U = update, T = truncate'';
COMMENT ON COLUMN audit.%1$s.row_data IS ''Record value. Null for statement-level trigger. For INSERT this is the new tuple. For DELETE and UPDATE it is the old tuple.'';
COMMENT ON COLUMN audit.%1$s.changed_fields IS ''New values of fields changed by UPDATE. Null except for row-level UPDATE events.'';
COMMENT ON COLUMN audit.%1$s.statement_only IS ''''''t'''' if audit event is from an FOR EACH STATEMENT trigger, ''''f'''' for FOR EACH ROW'';
CREATE INDEX %1$s_relid_idx ON audit.%1$s(relid);
CREATE INDEX %1$s_action_tstamp_tx_stm_idx ON audit.%1$s(action_tstamp_stm);
CREATE INDEX %1$s_action_idx ON audit.%1$s(action);
', table_names[i]);
EXECUTE format('
DROP TRIGGER IF EXISTS audit_trigger_row ON %1$s;
CREATE TRIGGER audit_trigger_row
AFTER INSERT OR UPDATE OR DELETE
ON public.%1$s
FOR EACH ROW
EXECUTE PROCEDURE audit.if_modified_func();', table_names[i]);
EXECUTE format('
DROP TRIGGER IF EXISTS audit_trigger_stm ON %1$s;
CREATE TRIGGER audit_trigger_stm
AFTER TRUNCATE
ON public.%1$s
FOR EACH STATEMENT
EXECUTE PROCEDURE audit.if_modified_func();', table_names[i]);
END LOOP;
RETURN 'SUCCESS';
END;
$BODY$
LANGUAGE plpgsql;
ALTER FUNCTION audit.create_audit_table(character varying[])
OWNER TO postgres;
UPDATE 03/31:
Ok, so I created the if_modified_func() function without the dynamic sql and I declared the audit_row as audit_row RECORD; I am not sure about the part of "needing a cast upon inserting the values". I am also not sure if this is the correct way to do the insert
EXECUTE format($string$INSERT INTO audit.%1$s VALUES (audit_row.*);$string$, TG_TABLE_NAME::text);
I am now getting this error when I run select audit.create_audit_table(ARRAY['organization'])
ERROR:
ERROR: record "audit_row" has no field "row_data"
CONTEXT: PL/pgSQL function audit.if_modified_func() line 42 at assignment
Here's the updated function:
CREATE OR REPLACE FUNCTION audit.if_modified_func() RETURNS TRIGGER AS $$
DECLARE
audit_row RECORD;
include_values boolean;
log_diffs boolean;
h_old hstore;
h_new hstore;
excluded_cols text[] = ARRAY[]::text[];
BEGIN
IF TG_WHEN <> 'AFTER' THEN
RAISE EXCEPTION 'audit.if_modified_func() may only run as an AFTER trigger';
END IF;
audit_row = ROW(
nextval(format('audit.%1$s_event_id_seq',TG_TABLE_NAME::text)), -- event_id
TG_TABLE_SCHEMA::text, -- schema_name
TG_TABLE_NAME::text, -- table_name
TG_RELID, -- relation OID for much quicker searches
session_user::text, -- session_user_name
current_timestamp, -- action_tstamp_tx
statement_timestamp(), -- action_tstamp_stm
clock_timestamp(), -- action_tstamp_clk
txid_current(), -- transaction ID
current_setting('application_name'), -- client application
inet_client_addr(), -- client_addr
inet_client_port(), -- client_port
current_query(), -- top-level query or queries (if multistatement) from client
substring(TG_OP,1,1), -- action
NULL, NULL, -- row_data, changed_fields
'f' -- statement_only
);
IF NOT TG_ARGV[0]::boolean IS DISTINCT FROM 'f'::boolean THEN
audit_row.client_query = NULL;
END IF;
IF TG_ARGV[1] IS NOT NULL THEN
excluded_cols = TG_ARGV[1]::text[];
END IF;
IF (TG_OP = 'UPDATE' AND TG_LEVEL = 'ROW') THEN
audit_row.row_data = hstore(OLD.*) - excluded_cols;
audit_row.changed_fields = (hstore(NEW.*) - audit_row.row_data) - excluded_cols;
IF audit_row.changed_fields = hstore('') THEN
-- All changed fields are ignored. Skip this update.
RETURN NULL;
END IF;
ELSIF (TG_OP = 'DELETE' AND TG_LEVEL = 'ROW') THEN
audit_row.row_data = hstore(OLD.*) - excluded_cols;
ELSIF (TG_OP = 'INSERT' AND TG_LEVEL = 'ROW') THEN
audit_row.row_data = hstore(NEW.*) - excluded_cols;
ELSIF (TG_LEVEL = 'STATEMENT' AND TG_OP IN ('INSERT','UPDATE','DELETE','TRUNCATE')) THEN
audit_row.statement_only = 't';
ELSE
RAISE EXCEPTION '[audit.if_modified_func] - Trigger func added as trigger for unhandled case: %, %',TG_OP, TG_LEVEL;
RETURN NULL;
END IF;
EXECUTE format('INSERT INTO audit.%1$s VALUES (audit_row.*)', TG_TABLE_NAME::text);
RETURN null;
END;
$$
LANGUAGE plpgsql;
ALTER FUNCTION audit.if_modified_func()
OWNER TO postgres;
TG_TABLE_NAME is a special, trigger variable, which is only available inside trigger functions. Your create_audit_table() is not a trigger function.
Also, you constantly redefining your real trigger function (if_modified_func()), which "invalidates" any earlier created triggers.
Create your trigger function without the dynamic SQL magic (dynamic SQL will only need to insert values to these audit tables). Then, you can add your audit logic to a table with:
CREATE TRIGGER audit_trigger_row
AFTER INSERT OR UPDATE OR DELETE
ON public.<your_table_name>
FOR EACH ROW
EXECUTE PROCEDURE <your_audit_trigger_function_name>();
You can put this (but only this -- maybe with drop if exists) inside a function, to allow attaching this audit logic more easily.
Notes:
Inside the trigger function, you cannot use a %ROWTYPE variable (because you don't know the exact table. you only have its name). The solution is simple: just use the RECORD type instead (you will need a cast upon inserting the values though).
Don't use single quotes for such long strings. Use the $your_keyword$<string_value>$your_keyword$ format instead. With possibly the format() function instead of just concatenating values. Your code will be much more readable.
Edit: to utilize your RECORD variable, you should either:
Initialize it with a structure. You can do this in your case with f.ex.
SELECT nextval('audit.'|| quote_ident(TG_TABLE_NAME) || '_event_id_seq') AS event_id,
TG_TABLE_SCHEMA AS schema_name,
TG_TABLE_NAME AS table_name,
TG_RELID AS relid,
session_user AS session_user_name,
current_timestamp AS action_tstamp_tx,
statement_timestamp() AS action_tstamp_stm,
clock_timestamp() AS action_tstamp_clk,
txid_current() AS transaction_id,
current_setting('application_name') AS application_name,
inet_client_addr() AS client_addr,
inet_client_port() AS client_port,
current_query() AS client_query,
substring(TG_OP, 1, 1) AS action,
NULL::hstore AS row_data,
NULL::hstore AS changed_fields,
FALSE AS statement_only
INTO audit_row;
Use the predefined names of the ROW() constructor. The first column's name if f1, the second's is f2, etc.
audit_row.f15 = hstore(OLD.*) - excluded_cols;
After choosing one of the above methods, you should insert the row like:
EXECUTE format('INSERT INTO audit.%1$s VALUES (($1::text::audit.%1$s).*)', quote_ident(TG_TABLE_NAME)) USING audit_row;
Note: even the cast to text is required due to the fact that EXECUTE cannot know the actual structure of audit_row.
http://rextester.com/GUAJ1339
quote_ident(TG_TABLE_NAME::TEXT) will apply necessary actions to correcty quote the argument as relation name.
I would recommend using execute format('statement') instead of concatinations, eg:
t=# do $$ begin raise info '%',format('I am %I, now is %L',current_user,now()); end;$$;
INFO: I am postgres, now is '2017-03-30 07:33:53.579476+00'
DO
Instead of:
t=# do $$ begin raise info '%','I am '||quote_ident(current_user)||', now is '||quote_ident(now()::text); end;$$;
INFO: I am postgres, now is "2017-03-30 07:36:20.495887+00"
DO
I've mapped a POCO to a view. When EF does an insert, it generates the following command...
INSERT INTO "public"."vw_place"("Name","Description","Point") VALUES ($1,$2,$3) RETURNING "PlaceId"
But the code, throws the following error...
{"A null store-generated value was returned for a non-nullable member
'PlaceId' of type 'DataAccess.Place'."}
Here is the trigger function that does the insert...
CREATE OR REPLACE FUNCTION vw_place_dml()
RETURNS trigger AS
$BODY$
BEGIN
IF TG_OP = 'INSERT' THEN
INSERT INTO tbl_place
(
"Name",
"Description",
"Point"
)
VALUES
(
NEW."Name",
NEW."Description",
ST_GeomFromWKB(NEW."Point", 4326)
);
RETURN NEW;
ELSIF TG_OP = 'UPDATE' THEN
UPDATE tbl_place SET
"PlaceId" = NEW."PlaceId",
"Name" = NEW."Name",
"Description" = NEW."Description",
"Point" = ST_GeomFromWKB(NEW."Point", 4326)
WHERE
"PlaceId" = OLD."PlaceId";
RETURN NEW;
END IF;
RETURN NEW;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
ALTER FUNCTION vw_place_dml()
OWNER TO postgres;
If I run this in pgAdmin it returns nothing, which is the problem, but the row is successfully inserted and a PlaceId is generated.
INSERT INTO "public"."vw_place"("Name","Description","Point") VALUES
('ergw','regr','\x0101000000000000009846b2bfe4e068d7ff33a73f')
RETURNING "PlaceId"
After the insert in the trigger function and before RETURN NEW;, I added...
NEW."PlaceId" = currval('"tbl_place_PlaceId_seq"');
I have these tables:
CREATE EXTENSION citext;
CREATE EXTENSION "uuid-ossp";
CREATE TABLE cities
(
city_id serial PRIMARY KEY,
city_name citext NOT NULL UNIQUE
);
INSERT INTO cities(city_name) VALUES
('New York'), ('Paris'), ('Madrid');
CREATE TABLE etags
(
etag_name varchar(128) PRIMARY KEY,
etag_value uuid
);
INSERT INTO etags(etag_name, etag_value)
VALUES ('cities', uuid_generate_v4());
I want to update the cities etag when the cities table changes. If no rows are affected by the insert, update or delete statement, I'd like to avoid to change the cities etag, so I wrote the following statement level trigger:
CREATE OR REPLACE FUNCTION update_etag()
RETURNS trigger AS
$BODY$
DECLARE
record_count integer;
vetag_name varchar(128);
BEGIN
GET DIAGNOSTICS record_count = ROW_COUNT;
vetag_name := TG_ARGV[0];
RAISE NOTICE 'affected %:%', vetag_name, record_count;
IF record_count = 0 THEN
RETURN NULL;
END IF;
UPDATE etags SET etag_value = uuid_generate_v4()
WHERE etag_name = vetag_name;
RETURN null;
END;
$BODY$
LANGUAGE plpgsql VOLATILE;
CREATE TRIGGER update_cities_etag_trigger
AFTER INSERT OR UPDATE OR DELETE
ON cities
FOR EACH STATEMENT
EXECUTE PROCEDURE update_etag('cities');
However GET DIAGNOSTICS record_count = ROW_COUNT; doesn't work for me, as it always returns 0.
If I execute the following:
DELETE FROM cities;
The following is output:
NOTICE: affected cities:0 Query returned successfully: 3 rows
affected, 47 msec execution time.
Is there a way to figure out how many rows are affected by the statement that triggers the trigger in a PostgreSQL statement-level trigger?
Version 10
CREATE TRIGGER
...
[ REFERENCING { { OLD | NEW } TABLE [ AS ] transition_relation_name } [ ... ] ]
...
https://www.postgresql.org/docs/current/static/release-10.html
Add AFTER trigger transition tables to record changed rows (Kevin
Grittner, Thomas Munro)
Transition tables are accessible from triggers written in server-side
languages.
Example
Solves it:
CREATE OR REPLACE FUNCTION update_etag()
RETURNS trigger AS
$BODY$
DECLARE
record_count integer;
vetag_name varchar(128);
begin
IF (TG_OP = 'DELETE') or (TG_OP = 'UPDATE') THEN
select count(*) from oldtbl into record_count ;
ELSE
select count(*) from newtbl into record_count ;
END IF;
vetag_name := TG_ARGV[0];
RAISE NOTICE 'affected %:%:%', vetag_name,TG_OP, record_count;
IF record_count = 0 THEN
RETURN NULL;
END IF;
UPDATE etags SET etag_value = uuid_generate_v4()
WHERE etag_name = vetag_name;
RETURN null;
END;
$BODY$
LANGUAGE plpgsql VOLATILE;
CREATE TRIGGER update_ins_cities_etag_trigger
AFTER INSERT
ON cities
REFERENCING NEW TABLE AS newtbl
FOR EACH STATEMENT
EXECUTE PROCEDURE update_etag('cities');
CREATE TRIGGER update_upd_cities_etag_trigger
AFTER UPDATE
ON cities
REFERENCING OLD TABLE AS oldtbl
FOR EACH STATEMENT
EXECUTE PROCEDURE update_etag('cities');
CREATE TRIGGER update_del_cities_etag_trigger
AFTER DELETE
ON cities
REFERENCING OLD TABLE AS oldtbl
FOR EACH STATEMENT
EXECUTE PROCEDURE update_etag('cities');
so=# INSERT INTO cities(city_name) VALUES
so-# ('New York'), ('Paris'), ('Madrid');
NOTICE: affected cities:INSERT:3
INSERT 0 3
so=# select * from etags;
etag_name | etag_value
-----------+--------------------------------------
cities | dc7d1525-eea7-4822-b736-5141a20764f8
(1 row)
so=# insert into cities(city_name) values ('Budapest');
NOTICE: affected cities:INSERT:1
INSERT 0 1
so=# select * from etags;
etag_name | etag_value
-----------+--------------------------------------
cities | df835f44-dada-4a94-bb62-5890f2316103
(1 row)
so=# delete from cities where city_id > 42;
NOTICE: affected cities:DELETE:0
DELETE 0
so=# select * from etags;
etag_name | etag_value
-----------+--------------------------------------
cities | df835f44-dada-4a94-bb62-5890f2316103
(1 row)