mirror of
https://github.com/LemmyNet/lemmy.git
synced 2024-11-25 13:51:19 +00:00
try to fix create_triggers
This commit is contained in:
dullbananas
GitHub
parent
75d00a4626
commit
b916ab9e31
1 changed files with 123 additions and 141 deletions
|
|
@ -36,74 +36,105 @@ BEGIN
|
|||
END
|
||||
$$;
|
||||
|
||||
-- Create functions that select both old and new rows in a trigger. Column 1 is `-1` if old and `1` if new,
|
||||
-- which can be used with `sum` to get the number to add to a count. Column 2 is the original row as a composite
|
||||
-- value. A separate function is called in each `IF` statement to prevent an error from referencing transition
|
||||
-- tables that don't exist. All of this could be one function, but that would require using `RETURN QUERY EXECUTE`
|
||||
-- instead of calls to separate functions because of PostgreSQL's limited polymorphism. Parsing and planning dynamic
|
||||
-- queries at runtime is worse for performance.
|
||||
CREATE PROCEDURE r.combine_transition_tables_function (table_name text)
|
||||
-- This function creates statement-level triggers for all operation types. It's designed this way
|
||||
-- because of these limitations:
|
||||
-- * A trigger that uses transition tables can only handle 1 operation type.
|
||||
-- * Transition tables must be relevant for the operation type (for example, `NEW TABLE` is
|
||||
-- not allowed for a `DELETE` trigger)
|
||||
-- * Transition tables are only provided to the trigger function, not to functions that it calls.
|
||||
--
|
||||
-- This function can only be called once per table. The command to run is given as the 2nd argument
|
||||
-- and has access to these tables:
|
||||
-- * `old_table` with old rows
|
||||
-- * `new_table` with new rows
|
||||
-- * `combined_transition_tables` with both old and new rows, with 2 columns:
|
||||
-- 1. `-1` for old rows and `1` for new rows, which can be used with `sum` to get the number
|
||||
-- to add to a count
|
||||
-- 2. the old or new row as a composite value
|
||||
CREATE PROCEDURE r.create_triggers (table_name text, command text)
|
||||
LANGUAGE plpgsql
|
||||
AS $a$
|
||||
BEGIN
|
||||
EXECUTE replace($b$
|
||||
CREATE FUNCTION r.get_old_thing_rows ()
|
||||
RETURNS SETOF record
|
||||
DECLARE
|
||||
defs text := $b$
|
||||
CREATE FUNCTION r.thing_delete_statement ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
RETURN QUERY SELECT -1, old_table FROM old_table;
|
||||
RETURN;
|
||||
PERFORM (
|
||||
WITH
|
||||
combined_transition_tables AS (
|
||||
select_old_table
|
||||
),
|
||||
trigger_result AS command
|
||||
SELECT
|
||||
1
|
||||
);
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
CREATE FUNCTION r.get_new_thing_rows ()
|
||||
RETURNS SETOF record
|
||||
CREATE TRIGGER delete_statement
|
||||
AFTER DELETE ON thing REFERENCING OLD TABLE AS old_table
|
||||
FOR EACH STATEMENT
|
||||
EXECUTE FUNCTION r.thing_delete_statement ();
|
||||
CREATE FUNCTION r.thing_insert_statement ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
RETURN QUERY SELECT 1, new_table FROM new_table;
|
||||
RETURN;
|
||||
PERFORM (
|
||||
WITH
|
||||
combined_transition_tables AS (
|
||||
select_new_table
|
||||
),
|
||||
trigger_result AS command
|
||||
SELECT
|
||||
1
|
||||
);
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
CREATE FUNCTION r.combine_thing_transition_tables (tg_op text)
|
||||
RETURNS SETOF record
|
||||
CREATE TRIGGER insert_statement
|
||||
AFTER DELETE ON thing REFERENCING NEW TABLE AS new_table
|
||||
FOR EACH STATEMENT
|
||||
EXECUTE FUNCTION r.thing_insert_statement ();
|
||||
CREATE FUNCTION r.thing_update_statement ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
IF (TG_OP IN ('UPDATE', 'DELETE')) THEN
|
||||
RETURN QUERY SELECT * FROM r.get_old_thing_rows () AS (count_diff bigint, thing thing);
|
||||
END IF;
|
||||
IF (TG_OP IN ('UPDATE', 'INSERT')) THEN
|
||||
RETURN QUERY SELECT * FROM r.get_new_thing_rows () AS (count_diff bigint, thing thing);
|
||||
END IF;
|
||||
RETURN;
|
||||
PERFORM (
|
||||
WITH
|
||||
combined_transition_tables AS (
|
||||
select_old_table
|
||||
UNION ALL
|
||||
select_new_table
|
||||
),
|
||||
trigger_result AS command
|
||||
SELECT
|
||||
1
|
||||
);
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
$b$, 'thing', table_name);
|
||||
CREATE TRIGGER update_statement
|
||||
AFTER UPDATE ON thing REFERENCING OLD TABLE AS old_table NEW TABLE AS new_table
|
||||
FOR EACH STATEMENT
|
||||
EXECUTE FUNCTION r.thing_update_statement ();
|
||||
$b$;
|
||||
BEGIN
|
||||
defs := replace(defs, 'select_old_table', $$
|
||||
SELECT -1 AS count_diff, old_table AS thing FROM old_table
|
||||
$$);
|
||||
defs := replace(defs, 'select_new_table', $$
|
||||
SELECT 1 AS count_diff, new_table AS thing FROM new_table
|
||||
$$);
|
||||
defs := replace(defs, 'thing', table_name);
|
||||
defs := replace(defs, 'command', format('(%s)', command));
|
||||
EXECUTE defs;
|
||||
END
|
||||
$a$;
|
||||
|
||||
CALL r.combine_transition_tables_function('comment');
|
||||
|
||||
CALL r.combine_transition_tables_function('community');
|
||||
|
||||
CALL r.combine_transition_tables_function('community_follower');
|
||||
|
||||
CALL r.combine_transition_tables_function('person');
|
||||
|
||||
CALL r.combine_transition_tables_function('post');
|
||||
|
||||
-- Creates triggers for all operation types, which can't be 1 trigger when transition tables are used
|
||||
CREATE PROCEDURE r.create_triggers (table_name text, function_name text)
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
EXECUTE format('CREATE TRIGGER %2$s_insert AFTER INSERT ON %1$s REFERENCING NEW TABLE AS new_table FOR EACH STATEMENT EXECUTE FUNCTION r.%2$s ();', table_name, function_name);
|
||||
EXECUTE format('CREATE TRIGGER %2$s_delete AFTER DELETE ON %1$s REFERENCING OLD TABLE AS old_table FOR EACH STATEMENT EXECUTE FUNCTION r.%2$s ();', table_name, function_name);
|
||||
EXECUTE format('CREATE TRIGGER %2$s_update AFTER UPDATE ON %1$s REFERENCING OLD TABLE AS old_table NEW TABLE AS new_table FOR EACH STATEMENT EXECUTE FUNCTION r.%2$s ();', table_name, function_name);
|
||||
END
|
||||
$$;
|
||||
|
||||
-- Define functions
|
||||
CREATE FUNCTION r.creator_id_from_post_aggregates (agg post_aggregates)
|
||||
RETURNS int RETURN agg.creator_id;
|
||||
|
|
@ -149,11 +180,7 @@ BEGIN
|
|||
FOR EACH STATEMENT
|
||||
EXECUTE FUNCTION r.resolve_reports_when_thing_removed ( );
|
||||
-- When a thing gets a vote, update its aggregates and its creator's aggregates
|
||||
CREATE FUNCTION r.thing_aggregates_from_like ( )
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
CALL r.create_triggers ('thing_like', $$
|
||||
WITH thing_diff AS (
|
||||
UPDATE
|
||||
thing_aggregates AS a
|
||||
|
|
@ -168,7 +195,7 @@ BEGIN
|
|||
sum(count_diff) FILTER (WHERE (thing_like).score = 1) AS upvotes,
|
||||
sum(count_diff) FILTER (WHERE (thing_like).score != 1) AS downvotes
|
||||
FROM
|
||||
r.combine_thing_transition_tables (TG_OP)
|
||||
combined_transition_tables
|
||||
AS (count_diff bigint,
|
||||
thing_like thing_like)
|
||||
GROUP BY
|
||||
|
|
@ -191,13 +218,8 @@ BEGIN
|
|||
GROUP BY
|
||||
creator_id) AS diff
|
||||
WHERE
|
||||
a.person_id = diff.creator_id;
|
||||
RETURN NULL;
|
||||
END $$;
|
||||
CALL r.create_triggers ('thing_like', 'thing_aggregates_from_like');
|
||||
$b$,
|
||||
'thing',
|
||||
thing_type);
|
||||
a.person_id = diff.creator_id
|
||||
$$);
|
||||
END
|
||||
$a$;
|
||||
|
||||
|
|
@ -206,11 +228,7 @@ CALL r.post_or_comment ('post');
|
|||
CALL r.post_or_comment ('comment');
|
||||
|
||||
-- Create triggers that update counts in parent aggregates
|
||||
CREATE FUNCTION r.parent_aggregates_from_comment ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
CALL r.create_triggers('comment', $$
|
||||
WITH comment_group AS (
|
||||
SELECT
|
||||
(comment).post_id,
|
||||
|
|
@ -218,7 +236,7 @@ BEGIN
|
|||
(comment).local,
|
||||
sum(count_diff) AS comments
|
||||
FROM
|
||||
r.combine_comment_transition_tables (TG_OP)
|
||||
combined_transition_tables
|
||||
AS (count_diff bigint,
|
||||
comment comment)
|
||||
WHERE
|
||||
|
|
@ -302,18 +320,10 @@ FROM (
|
|||
GROUP BY
|
||||
community_id) AS diff
|
||||
WHERE
|
||||
a.community_id = diff.community_id;
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
a.community_id = diff.community_id
|
||||
$$);
|
||||
|
||||
CALL r.create_triggers ('comment', 'parent_aggregates_from_comment');
|
||||
|
||||
CREATE FUNCTION r.parent_aggregates_from_post ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
CALL r.create_triggers('post', $$
|
||||
WITH post_group AS (
|
||||
SELECT
|
||||
(post).community_id,
|
||||
|
|
@ -321,7 +331,7 @@ BEGIN
|
|||
(post).local,
|
||||
sum(count_diff) AS posts
|
||||
FROM
|
||||
r.combine_post_transition_tables (TG_OP)
|
||||
combined_post_transition_tables
|
||||
AS (count_diff bigint,
|
||||
post post)
|
||||
WHERE
|
||||
|
|
@ -357,18 +367,10 @@ SET
|
|||
FROM
|
||||
post_group
|
||||
WHERE
|
||||
a.community_id = post_group.community_id;
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
a.community_id = post_group.community_id
|
||||
$$);
|
||||
|
||||
CALL r.create_triggers ('post', 'parent_aggregates_from_post');
|
||||
|
||||
CREATE FUNCTION r.site_aggregates_from_community ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
CALL r.create_triggers('community', $$
|
||||
UPDATE
|
||||
site_aggregates AS a
|
||||
SET
|
||||
|
|
@ -377,20 +379,12 @@ BEGIN
|
|||
SELECT
|
||||
sum(count_diff) AS communities
|
||||
FROM
|
||||
r.combine_community_transition_tables (TG_OP)
|
||||
combined_transition_tables
|
||||
AS (count_diff bigint, community community)
|
||||
WHERE (community).local AND NOT ((community).deleted OR (community).removed)) AS diff;
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
WHERE (community).local AND NOT ((community).deleted OR (community).removed)) AS diff
|
||||
$$);
|
||||
|
||||
CALL r.create_triggers ('community', 'site_aggregates_from_community');
|
||||
|
||||
CREATE FUNCTION r.site_aggregates_from_person ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
CALL r.create_triggers('person', $$
|
||||
UPDATE
|
||||
site_aggregates AS a
|
||||
SET
|
||||
|
|
@ -399,14 +393,10 @@ BEGIN
|
|||
SELECT
|
||||
sum(count_diff) AS users
|
||||
FROM
|
||||
r.combine_person_transition_tables (TG_OP)
|
||||
combined_transition_tables
|
||||
AS (count_diff bigint, person person)
|
||||
WHERE (person).local) AS diff;
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
|
||||
CALL r.create_triggers ('person', 'site_aggregates_from_person');
|
||||
WHERE (person).local) AS diff
|
||||
$$);
|
||||
|
||||
-- For community_aggregates.comments, don't include comments of deleted or removed posts
|
||||
CREATE FUNCTION r.update_comment_count_from_post ()
|
||||
|
|
@ -456,11 +446,7 @@ CREATE TRIGGER comment_count
|
|||
EXECUTE FUNCTION r.update_comment_count_from_post ();
|
||||
|
||||
-- Count subscribers for local communities
|
||||
CREATE FUNCTION r.community_aggregates_from_subscriber ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
AS $$
|
||||
BEGIN
|
||||
CALL r.create_triggers ('community_follower', $$
|
||||
UPDATE
|
||||
community_aggregates AS a
|
||||
SET
|
||||
|
|
@ -470,7 +456,7 @@ BEGIN
|
|||
(community_follower).community_id,
|
||||
sum(count_diff) AS subscribers
|
||||
FROM
|
||||
r.combine_community_follower_transition_tables (TG_OP)
|
||||
combine_transition_tables
|
||||
AS (count_diff bigint, community_follower community_follower)
|
||||
WHERE (
|
||||
SELECT
|
||||
|
|
@ -483,12 +469,8 @@ BEGIN
|
|||
GROUP BY
|
||||
(community_follower).community_id) AS diff
|
||||
WHERE
|
||||
a.community_id = diff.community_id;
|
||||
RETURN NULL;
|
||||
END
|
||||
$$;
|
||||
|
||||
CALL r.create_triggers ('community_follower', 'community_aggregates_from_subscriber');
|
||||
a.community_id = diff.community_id
|
||||
$$);
|
||||
|
||||
-- These triggers create and update rows in each aggregates table to match its associated table's rows.
|
||||
-- Deleting rows and updating IDs are already handled by `CASCADE` in foreign key constraints.
|
||||
|
|
@ -581,6 +563,11 @@ BEGIN
|
|||
END
|
||||
$$;
|
||||
|
||||
CREATE TRIGGER aggregates
|
||||
AFTER INSERT ON post REFERENCING NEW TABLE AS new_post
|
||||
FOR EACH STATEMENT
|
||||
EXECUTE FUNCTION r.post_aggregates_from_post ();
|
||||
|
||||
CREATE FUNCTION r.post_aggregates_from_post_update ()
|
||||
RETURNS TRIGGER
|
||||
LANGUAGE plpgsql
|
||||
|
|
@ -599,11 +586,6 @@ BEGIN
|
|||
END
|
||||
$$;
|
||||
|
||||
CREATE TRIGGER aggregates
|
||||
AFTER INSERT ON post REFERENCING NEW TABLE AS new_post
|
||||
FOR EACH STATEMENT
|
||||
EXECUTE FUNCTION r.post_aggregates_from_post ();
|
||||
|
||||
CREATE TRIGGER aggregates_update
|
||||
AFTER UPDATE ON post REFERENCING NEW TABLE AS new_post
|
||||
FOR EACH STATEMENT
|
||||
|
|
|
|||
Loading…
Reference in a new issue