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Thread: Triggers and Full Text Search *

Triggers and Full Text Search *

From
Malik Rumi
Date:

More than a year ago, I implemented full text search on one of my sites. From the beginning, there was one problem (or at least, what I perceive to be a problem): when I use a script to insert many documents at once, they do *not* get indexed in fts. If a document is created or inserted one at a time, fts indexes immediately. The workaround I came up with was just to open each of those script inserted documents and then close them. As soon as they are opened, they get indexed. 

I assume this has to do with the trigger, which is set to BEFORE, and which I carefully followed from the blog post that I got the code from. I wrote to that author at the time, but he was of no help. My thought was that the trigger was not firing, and thus the documents were not getting indexed, because until the document was actually there, there was nothing to index. Therefore, I thought a simple switch from BEFORE to AFTER would solve my problem. However, in the example in the official docs, BEFORE is used as well, so I abandoned that idea and decided to post this question.  

Another solution I had in mind was to simply include an additional step in my insert script to sleep for one second, during which the current document would be opened, and hopefully indexed, and then closed, so the script could go on to the next document. Note my insert script is in Python and goes through Django. This is not a ‘pure’ postgresql operation, if that matters.

My questions are:

  1. Does this sleep / open / close / proceed idea seem like a workable solution?

  2. Is there a better workaround?

  3. At first blush, I would think the speed of insertion would not be an issue for any trigger - it would seem to defeat the purpose - but am I wrong about that? 


I am not (yet) posting the trigger code because this post is long already, and if your answers are 1) yes, 2) no and 3) triggers often work / fail like this, then there’s no point and we can wrap this up. But if not, I will happily post what I have. Thank you.





“None of you has faith until he loves for his brother or his neighbor what he loves for himself.”

Sv: Triggers and Full Text Search *

From
Andreas Joseph Krogh
Date:
På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi <malik.a.rumi@gmail.com>:

[...]

I am not (yet) posting the trigger code because this post is long already, and if your answers are 1) yes, 2) no and 3) triggers often work / fail like this, then there’s no point and we can wrap this up. But if not, I will happily post what I have. Thank you.

 
This is too much prose for the regular programmer, show us the code, and point out what doesn't work for you, then we can help:-)
 
--
Andreas Joseph Krogh

Re: Triggers and Full Text Search *

From
Ericson Smith
Date:
I think COPY bypasses the triggers.

Best Regards
- Ericson Smith
+1 876-375-9857 (whatsapp)
+1 646-483-3420 (sms)



On Wed, Apr 22, 2020 at 12:32 AM Andreas Joseph Krogh <andreas@visena.com> wrote:
På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi <malik.a.rumi@gmail.com>:

[...]

I am not (yet) posting the trigger code because this post is long already, and if your answers are 1) yes, 2) no and 3) triggers often work / fail like this, then there’s no point and we can wrap this up. But if not, I will happily post what I have. Thank you.

 
This is too much prose for the regular programmer, show us the code, and point out what doesn't work for you, then we can help:-)
 
--
Andreas Joseph Krogh

Re: Triggers and Full Text Search *

From
Adrian Klaver
Date:
On 4/21/20 11:04 AM, Ericson Smith wrote:
> I think COPY bypasses the triggers.

No:

https://www.postgresql.org/docs/12/sql-copy.html

"COPY FROM will invoke any triggers and check constraints on the 
destination table. However, it will not invoke rules."

> 
> Best Regards
> - Ericson Smith
> +1 876-375-9857 (whatsapp)
> +1 646-483-3420 (sms)
> 
> 
> 
> On Wed, Apr 22, 2020 at 12:32 AM Andreas Joseph Krogh 
> <andreas@visena.com <mailto:andreas@visena.com>> wrote:
> 
>     På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi
>     <malik.a.rumi@gmail.com <mailto:malik.a.rumi@gmail.com>>:
> 
>         [...]
> 
>         I am not (yet) posting the trigger code because this post is
>         long already, and if your answers are 1) yes, 2) no and 3)
>         triggers often work / fail like this, then there’s no point and
>         we can wrap this up. But if not, I will happily post what I
>         have. Thank you.
> 
>     This is too much prose for the regular programmer, show us the code,
>     and point out what doesn't work for you, then we can help:-)
>     --
>     Andreas Joseph Krogh
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com

Re: Triggers and Full Text Search *

From
Malik Rumi
Date:
@Ericson,
Forgive me for seeming dense, but how does COPY help or hurt here?

@Andreas,
I had to laugh at your reference to "prose". Would you believe I am actually a published playwright? Long before I started coding, of course. Old habits die hard.....

entry_search_vector_trigger
            BEGIN
              SELECT setweight(to_tsvector(NEW.title), 'A') ||
                     setweight(to_tsvector(NEW.content), 'B') ||
                     setweight(to_tsvector(NEW.category), 'D') ||
                     setweight(to_tsvector(COALESCE(string_agg(tag.tag, ', '), '')), 'C')
              INTO NEW.search_vector
              FROM ktab_entry AS entry
                LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
                LEFT JOIN ktab_tag AS tag ON tag.id = entry_tags.tag_id
              WHERE entry.id = NEW.id
              GROUP BY entry.id, category;
              RETURN NEW;
            END;
       
tag_search_vector_trigger
            BEGIN
              UPDATE ktab_entry SET id = id WHERE id IN (
                SELECT entry_id FROM ktab_entry_tags WHERE tag_id = NEW.id
              );
              RETURN NEW;
            END;
            
tags_search_vector_trigger
            BEGIN
              IF (TG_OP = 'DELETE') THEN
                UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
                RETURN OLD;
              ELSE
                UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
                RETURN NEW;
              END IF;
            END;
            
search_vector_update
            BEGIN
              SELECT setweight(to_tsvector(NEW.title), 'A') ||
                     setweight(to_tsvector(NEW.content), 'B') ||
                     setweight(to_tsvector(NEW.category), 'D') ||
                     setweight(to_tsvector(COALESCE(string_agg(tag.tag, ', '), '')), 'C')
              INTO NEW.search_vector
              FROM ktab_entry AS entry
                LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
                LEFT JOIN ktab_tag AS tag ON tag.id = entry_tags.tag_id
              WHERE entry.id = NEW.id
              GROUP BY entry.id, category;
              RETURN NEW;
            END;
            
search_vector_update  (tags)
            BEGIN
              IF (TG_OP = 'DELETE') THEN
                UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
                RETURN OLD;
              ELSE
                UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
                RETURN NEW;
              END IF;
            END;
            
Thank you!



“None of you has faith until he loves for his brother or his neighbor what he loves for himself.”


On Tue, Apr 21, 2020 at 1:05 PM Ericson Smith <esconsult1@gmail.com> wrote:
I think COPY bypasses the triggers.

Best Regards
- Ericson Smith
+1 876-375-9857 (whatsapp)
+1 646-483-3420 (sms)



On Wed, Apr 22, 2020 at 12:32 AM Andreas Joseph Krogh <andreas@visena.com> wrote:
På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi <malik.a.rumi@gmail.com>:

[...]

I am not (yet) posting the trigger code because this post is long already, and if your answers are 1) yes, 2) no and 3) triggers often work / fail like this, then there’s no point and we can wrap this up. But if not, I will happily post what I have. Thank you.

 
This is too much prose for the regular programmer, show us the code, and point out what doesn't work for you, then we can help:-)
 
--
Andreas Joseph Krogh

Re: Triggers and Full Text Search *

From
Ericson Smith
Date:
My apologies - I did not look closely at the manual. Many many years ago (6.xx days I had a similar problem and leapt to answer).

Could you post your CREATE TRIGGER statements as well?


On Wed, Apr 22, 2020 at 1:21 AM Malik Rumi <malik.a.rumi@gmail.com> wrote:
@Ericson,
Forgive me for seeming dense, but how does COPY help or hurt here?

@Andreas,
I had to laugh at your reference to "prose". Would you believe I am actually a published playwright? Long before I started coding, of course. Old habits die hard.....

entry_search_vector_trigger
            BEGIN
              SELECT setweight(to_tsvector(NEW.title), 'A') ||
                     setweight(to_tsvector(NEW.content), 'B') ||
                     setweight(to_tsvector(NEW.category), 'D') ||
                     setweight(to_tsvector(COALESCE(string_agg(tag.tag, ', '), '')), 'C')
              INTO NEW.search_vector
              FROM ktab_entry AS entry
                LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
                LEFT JOIN ktab_tag AS tag ON tag.id = entry_tags.tag_id
              WHERE entry.id = NEW.id
              GROUP BY entry.id, category;
              RETURN NEW;
            END;
       
tag_search_vector_trigger
            BEGIN
              UPDATE ktab_entry SET id = id WHERE id IN (
                SELECT entry_id FROM ktab_entry_tags WHERE tag_id = NEW.id
              );
              RETURN NEW;
            END;
            
tags_search_vector_trigger
            BEGIN
              IF (TG_OP = 'DELETE') THEN
                UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
                RETURN OLD;
              ELSE
                UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
                RETURN NEW;
              END IF;
            END;
            
search_vector_update
            BEGIN
              SELECT setweight(to_tsvector(NEW.title), 'A') ||
                     setweight(to_tsvector(NEW.content), 'B') ||
                     setweight(to_tsvector(NEW.category), 'D') ||
                     setweight(to_tsvector(COALESCE(string_agg(tag.tag, ', '), '')), 'C')
              INTO NEW.search_vector
              FROM ktab_entry AS entry
                LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
                LEFT JOIN ktab_tag AS tag ON tag.id = entry_tags.tag_id
              WHERE entry.id = NEW.id
              GROUP BY entry.id, category;
              RETURN NEW;
            END;
            
search_vector_update  (tags)
            BEGIN
              IF (TG_OP = 'DELETE') THEN
                UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
                RETURN OLD;
              ELSE
                UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
                RETURN NEW;
              END IF;
            END;
            
Thank you!



“None of you has faith until he loves for his brother or his neighbor what he loves for himself.”


On Tue, Apr 21, 2020 at 1:05 PM Ericson Smith <esconsult1@gmail.com> wrote:
I think COPY bypasses the triggers.

Best Regards
- Ericson Smith
+1 876-375-9857 (whatsapp)
+1 646-483-3420 (sms)



On Wed, Apr 22, 2020 at 12:32 AM Andreas Joseph Krogh <andreas@visena.com> wrote:
På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi <malik.a.rumi@gmail.com>:

[...]

I am not (yet) posting the trigger code because this post is long already, and if your answers are 1) yes, 2) no and 3) triggers often work / fail like this, then there’s no point and we can wrap this up. But if not, I will happily post what I have. Thank you.

 
This is too much prose for the regular programmer, show us the code, and point out what doesn't work for you, then we can help:-)
 
--
Andreas Joseph Krogh

Re: Triggers and Full Text Search *

From
Adrian Klaver
Date:
On 4/21/20 11:21 AM, Malik Rumi wrote:
> @Ericson,
> Forgive me for seeming dense, but how does COPY help or hurt here?
> 
> @Andreas,
> I had to laugh at your reference to "prose". Would you believe I am 
> actually a published playwright? Long before I started coding, of 
> course. Old habits die hard.....

The script code via Python/Django/psycopg2 would be helpful as my 
suspicion is that you are seeing the effects of open transactions.

> 
> entry_search_vector_trigger
>              BEGIN
>                SELECT setweight(to_tsvector(NEW.title), 'A') ||
>                       setweight(to_tsvector(NEW.content), 'B') ||
>                       setweight(to_tsvector(NEW.category), 'D') ||
>                       setweight(to_tsvector(COALESCE(string_agg(tag.tag, 
> ', '), '')), 'C')
>                INTO NEW.search_vector
>                FROM ktab_entry AS entry
>                  LEFT JOIN ktab_entry_tags AS entry_tags ON 
> entry_tags.entry_id = entry.id <http://entry.id>
>                  LEFT JOIN ktab_tag AS tag ON tag.id <http://tag.id> = 
> entry_tags.tag_id
>                WHERE entry.id <http://entry.id> = NEW.id
>                GROUP BY entry.id <http://entry.id>, category;
>                RETURN NEW;
>              END;
> 
> tag_search_vector_trigger
>              BEGIN
>                UPDATE ktab_entry SET id = id WHERE id IN (
>                  SELECT entry_id FROM ktab_entry_tags WHERE tag_id = NEW.id
>                );
>                RETURN NEW;
>              END;
> 
> tags_search_vector_trigger
>              BEGIN
>                IF (TG_OP = 'DELETE') THEN
>                  UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
>                  RETURN OLD;
>                ELSE
>                  UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
>                  RETURN NEW;
>                END IF;
>              END;
> 
> search_vector_update
>              BEGIN
>                SELECT setweight(to_tsvector(NEW.title), 'A') ||
>                       setweight(to_tsvector(NEW.content), 'B') ||
>                       setweight(to_tsvector(NEW.category), 'D') ||
>                       setweight(to_tsvector(COALESCE(string_agg(tag.tag, 
> ', '), '')), 'C')
>                INTO NEW.search_vector
>                FROM ktab_entry AS entry
>                  LEFT JOIN ktab_entry_tags AS entry_tags ON 
> entry_tags.entry_id = entry.id <http://entry.id>
>                  LEFT JOIN ktab_tag AS tag ON tag.id <http://tag.id> = 
> entry_tags.tag_id
>                WHERE entry.id <http://entry.id> = NEW.id
>                GROUP BY entry.id <http://entry.id>, category;
>                RETURN NEW;
>              END;
> 
> search_vector_update  (tags)
>              BEGIN
>                IF (TG_OP = 'DELETE') THEN
>                  UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
>                  RETURN OLD;
>                ELSE
>                  UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
>                  RETURN NEW;
>                END IF;
>              END;
> 
> Thank you!
> 
> 
> 
> */“None of you has faith until he loves for his brother or his neighbor 
> what he loves for himself.”/*
> 
> 
> On Tue, Apr 21, 2020 at 1:05 PM Ericson Smith <esconsult1@gmail.com 
> <mailto:esconsult1@gmail.com>> wrote:
> 
>     I think COPY bypasses the triggers.
> 
>     Best Regards
>     - Ericson Smith
>     +1 876-375-9857 (whatsapp)
>     +1 646-483-3420 (sms)
> 
> 
> 
>     On Wed, Apr 22, 2020 at 12:32 AM Andreas Joseph Krogh
>     <andreas@visena.com <mailto:andreas@visena.com>> wrote:
> 
>         På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi
>         <malik.a.rumi@gmail.com <mailto:malik.a.rumi@gmail.com>>:
> 
>             [...]
> 
>             I am not (yet) posting the trigger code because this post is
>             long already, and if your answers are 1) yes, 2) no and 3)
>             triggers often work / fail like this, then there’s no point
>             and we can wrap this up. But if not, I will happily post
>             what I have. Thank you.
> 
>         This is too much prose for the regular programmer, show us the
>         code, and point out what doesn't work for you, then we can help:-)
>         --
>         Andreas Joseph Krogh
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com

Re: Triggers and Full Text Search *

From
Laurenz Albe
Date:
On Tue, 2020-04-21 at 12:24 -0500, Malik Rumi wrote:
> More than a year ago, I implemented full text search on one of my sites.
> From the beginning, there was one problem (or at least, what I perceive
> to be a problem): when I use a script to insert many documents at once,
> they do *not* get indexed in fts. If a document is created or inserted
> one at a time, fts indexes immediately. The workaround I came up with
> was just to open each of those script inserted documents and then close
> them. As soon as they are opened, they get indexed. 

A trigger will fire and update the index immediately.

That opening and closing you are talking about does not sound like
a database activity.  Rather, it sounds like your software is delaying
the actual insert into the database, which would of course explain
why you cannot find it in the index.

Yours,
Laurenz Albe
-- 
Cybertec | https://www.cybertec-postgresql.com

Re: Triggers and Full Text Search *

From
Malik Rumi
Date:
@Ericson
I have the script (statements?) by which I created the triggers, but since you asked I do not see them in pga4, from which I manage my postgres. I don't know if this is significant or not. Also, this was originally done quite a while ago, so my memory may be fuzzy. From the text of the statement "runSQL..." I think I ran this in the terminal. So this is the closest thing I can find to your request. The text that I previously posted can be found in 'triggers functions' under this schema in pga4, but not these statements. Also, further up the pga4 tree, "event triggers" is blank. I mention these things because I am not sure of their importance. Thanks.

triggers.py

# Trigger on insert or update of ktab.Entry

migrations.RunSQL('''CREATE OR REPLACE FUNCTION entry_search_vector_trigger() RETURNS trigger AS $$
BEGIN
  SELECT setweight(to_tsvector(NEW.title), 'A') ||
         setweight(to_tsvector(NEW.content), 'B') ||
         setweight(to_tsvector(NEW.category), 'D') ||
         setweight(to_tsvector(COALESCE(string_agg(tags.tag, ', '), '')), 'C')
  INTO NEW.search_vector
  FROM ktab_entry AS entry
    LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
    LEFT JOIN ktab_tags AS tag ON tag.id = entry_tags.tag_id
  WHERE entry.id = NEW.id
  GROUP BY entry.id, category;
  RETURN NEW;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER search_vector_update BEFORE INSERT OR UPDATE ON ktab_entry
  FOR EACH ROW EXECUTE PROCEDURE entry_search_vector_trigger();''')

# Trigger after ktab.Author is updated
'''
Since I don't have author, and besides, his author was a separate table - SKIP
CREATE OR REPLACE FUNCTION author_search_vector_trigger() RETURNS trigger AS $$
BEGIN
  UPDATE ktab_entry SET id = id WHERE author_id = NEW.id;
  RETURN NEW;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER search_vector_update AFTER INSERT OR UPDATE ON ktab_author
  FOR EACH ROW EXECUTE PROCEDURE author_search_vector_trigger();
'''

# Trigger after ktab.Entry.tags are added, deleted from a entry
migrations.RunSQL('''CREATE OR REPLACE FUNCTION tags_search_vector_trigger() RETURNS trigger AS $$
BEGIN
  IF (TG_OP = 'DELETE') THEN
    UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
    RETURN OLD;
  ELSE
    UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
    RETURN NEW;
  END IF;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER search_vector_update AFTER INSERT OR UPDATE OR DELETE ON ktab_entry_tags
  FOR EACH ROW EXECUTE PROCEDURE tags_search_vector_trigger();
''')

# Trigger after ktab.Tag is updated
migrations.RunSQL('''CREATE OR REPLACE FUNCTION tag_search_vector_trigger() RETURNS trigger AS $$
BEGIN
  UPDATE ktab_entry SET id = id WHERE id IN (
    SELECT entry_id FROM ktab_entry_tags WHERE tag_id = NEW.id
  );
  RETURN NEW;
END;
$$ LANGUAGE plpgsql;
CREATE TRIGGER search_vector_update AFTER UPDATE ON ktab_tag
  FOR EACH ROW EXECUTE PROCEDURE tag_search_vector_trigger();


“None of you has faith until he loves for his brother or his neighbor what he loves for himself.”


On Tue, Apr 21, 2020 at 1:25 PM Ericson Smith <esconsult1@gmail.com> wrote:
My apologies - I did not look closely at the manual. Many many years ago (6.xx days I had a similar problem and leapt to answer).

Could you post your CREATE TRIGGER statements as well?


On Wed, Apr 22, 2020 at 1:21 AM Malik Rumi <malik.a.rumi@gmail.com> wrote:
@Ericson,
Forgive me for seeming dense, but how does COPY help or hurt here?

@Andreas,
I had to laugh at your reference to "prose". Would you believe I am actually a published playwright? Long before I started coding, of course. Old habits die hard.....

entry_search_vector_trigger
            BEGIN
              SELECT setweight(to_tsvector(NEW.title), 'A') ||
                     setweight(to_tsvector(NEW.content), 'B') ||
                     setweight(to_tsvector(NEW.category), 'D') ||
                     setweight(to_tsvector(COALESCE(string_agg(tag.tag, ', '), '')), 'C')
              INTO NEW.search_vector
              FROM ktab_entry AS entry
                LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
                LEFT JOIN ktab_tag AS tag ON tag.id = entry_tags.tag_id
              WHERE entry.id = NEW.id
              GROUP BY entry.id, category;
              RETURN NEW;
            END;
       
tag_search_vector_trigger
            BEGIN
              UPDATE ktab_entry SET id = id WHERE id IN (
                SELECT entry_id FROM ktab_entry_tags WHERE tag_id = NEW.id
              );
              RETURN NEW;
            END;
            
tags_search_vector_trigger
            BEGIN
              IF (TG_OP = 'DELETE') THEN
                UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
                RETURN OLD;
              ELSE
                UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
                RETURN NEW;
              END IF;
            END;
            
search_vector_update
            BEGIN
              SELECT setweight(to_tsvector(NEW.title), 'A') ||
                     setweight(to_tsvector(NEW.content), 'B') ||
                     setweight(to_tsvector(NEW.category), 'D') ||
                     setweight(to_tsvector(COALESCE(string_agg(tag.tag, ', '), '')), 'C')
              INTO NEW.search_vector
              FROM ktab_entry AS entry
                LEFT JOIN ktab_entry_tags AS entry_tags ON entry_tags.entry_id = entry.id
                LEFT JOIN ktab_tag AS tag ON tag.id = entry_tags.tag_id
              WHERE entry.id = NEW.id
              GROUP BY entry.id, category;
              RETURN NEW;
            END;
            
search_vector_update  (tags)
            BEGIN
              IF (TG_OP = 'DELETE') THEN
                UPDATE ktab_entry SET id = id WHERE id = OLD.entry_id;
                RETURN OLD;
              ELSE
                UPDATE ktab_entry SET id = id WHERE id = NEW.entry_id;
                RETURN NEW;
              END IF;
            END;
            
Thank you!



“None of you has faith until he loves for his brother or his neighbor what he loves for himself.”


On Tue, Apr 21, 2020 at 1:05 PM Ericson Smith <esconsult1@gmail.com> wrote:
I think COPY bypasses the triggers.

Best Regards
- Ericson Smith
+1 876-375-9857 (whatsapp)
+1 646-483-3420 (sms)



On Wed, Apr 22, 2020 at 12:32 AM Andreas Joseph Krogh <andreas@visena.com> wrote:
På tirsdag 21. april 2020 kl. 19:24:10, skrev Malik Rumi <malik.a.rumi@gmail.com>:

[...]

I am not (yet) posting the trigger code because this post is long already, and if your answers are 1) yes, 2) no and 3) triggers often work / fail like this, then there’s no point and we can wrap this up. But if not, I will happily post what I have. Thank you.

 
This is too much prose for the regular programmer, show us the code, and point out what doesn't work for you, then we can help:-)
 
--
Andreas Joseph Krogh
Attachment