I have two columns with mySQL:
"part_no"
"pdf_link"
I need the "pdf_link" column to automatically grab/duplicate the "part_no" value and add a .pdf extension on the end.
For example: If part_no = 00-12345-998, then pdf_link = 00-12345-998.pdf
I need this to happen every time I insert.
I appreciate the help.
Erik
you can achive this effect by using triggers I think.
http://dev.mysql.com/doc/refman/5.0/en/trigger-syntax.html
CREATE TRIGGER ins_pdf AFTER INSERT ON MY_TABLE SET #pdf_link = concat(#part_no,'.pdf')
Why store this extra computed information in the database? You can do this in the query when you pull it out, or, if needed, you could make a view that does it only as-needed.
Example pseudo query (my brain hurts right now, so this is only an example):
select concat(`part_no`, ".pdf") as `pdf_link` from `parts`;
If you really need this, you could use a trigger to duplicate the data ans add the extra string.
Related
select count(*) FROM antecedente_delito WHERE rut_polichile = NEW.rut_polichile
this statement is giving de value 0, when it should give me 18 :/ ive been trying a lot to find any bug in it.
Here's the working solution that I mocked up using/changing your code in SqlFiddle. http://sqlfiddle.com/#!2/ac2e9/1
To trouble shoot this, I would view your actual values and verify that NEW. is returning what you think it should. Sometimes it may be doing some trims or removal of special characters, especially the _ and % signs are likely to stripped in subprocedures.
I would start with the query:
select top 50 rut_polichile, NEW.rut_plichile FROM antecedente_delito
If the issue is not obvious from that add in a varbinary check:
select top 50 cast( rut_polichile as varbinary), cast(NEW.rut_plichile as varbinary) from antecedente_delito
If the table only has 18 records, then you should be good to go with the above troubleshooting, but if there is more data, I would suggest limiting your results from the above by the rowid or other identifier in a where statement.
It's not the answer, but I hope it helps you find the answer.
The SELECT privilege for the subject table if references to table columns occur via OLD.col_name or NEW.col_name in the trigger definition.
but in your trigger i can't see any trigger definition. so try without NEW.
for more info: http://www.sqlinfo.net/mysqldocs/v51/triggers.html or
http://bugs.mysql.com/bug.php?id=31068
So I have a bunch of users in a column that get refreshed as:
Bill#test.comXYZ
Tom#test.comXYZ
John#test.comXYZ
We refresh the database each week and I need to update these appropriate emails to:
Bill#domain.com
Tom#domain.com
John#domain.com
I figured I can use concat to do the latter, but I am stuck on the former issue. Is there a way to split the values (like split Bill#test.comXYZ into Bill - #test.comXYZ and then remove the #TEXT values?).
Anyways, any help will be much appreciated.
You can use the mySQL replace function, i.e.
UPDATE mytable
set myfield = replace (myfield, '#test.comXYZ', 'domain.com')
http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace
I want to update a mysql row, but I do not want to specify all the column names.
The table has 9 rows and I always want to update the last 7 rows in the right order.
These are the Fields
id
projectid
fangate
home
thanks
overview
winner
modules.wallPost
modules.overviewParticipant
Is there any way I can update the last few records without specifying their names?
With an INSERT statement this can be done pretty easily by doing this:
INSERT INTO `settings`
VALUES (NULL, ...field values...)
So I was hoping I could do something like this:
UPDATE `settings`
VALUES (NULL, ...field values...)
WHERE ...statement...
But unfortunately that doesn't work.
If the two first columns make up the primary key (or a unique index) you could use replace
So basically instead of writing
UPDATE settings
SET fangate = $fangate,
home = $home,
thanks = $thanks
overview = $overview,
winner = $winner,
modules.wallPost = $modules.wallPost,
modules.overviewParticipant = $modules.overviewParticipant
WHERE id = $id AND procjectId = $projectId
You will write
REPLACE INTO settings
VALUES ($id,
$projectId,
$fangate,
$home,
$thanks
$overview,
$winner,
$modules.wallPost,
$modules.overviewParticipant)
Of course this only works if the row already exist, otherwise it will be created. Also, it will cause a DELETE and an INSERT behind the scene, if that matters.
You can't. You always have to specify the column names, because UPDATE doesn't edit a whole row, it edits specified columns.
Here's a link with the UPDATE syntax:
http://dev.mysql.com/doc/refman/5.0/en/update.html
No, it works on the INSERT because even if you didn't specify the column name but you have supplied all values in the VALUE clause. Now, in UPDATE, you need to specify which column name will the value be associated.
UPDATE syntax requires the column names that will be modified.
Are you always updating the same table and columns?
In that case one way would be to define a stored procedure in your schema.
That way you could just do:
CALL update_settings(id, projectid, values_of_last_7 ..);
Although you would have to create the procedure, check the Mysql web pages for how to do this, eg:
http://docs.oracle.com/cd/E17952_01/refman-5.0-en/create-procedure.html
I'm afraid you can't afford not specifying the column names.
You can refer to the update documentation here.
I am using DBIx::Class and I would like to only update one row in my table. Currently this is how I do it:
my $session = my_app->model("DB::Session")->find(1);
$session->update({done_yn=>'y',end_time=>\'NOW()'});
It works, but the problem is that when it does find to find the row, it does this whole query:
SELECT me.id, me.project_id, me.user_id, me.start_time, me.end_time, me.notes, me.done_yn FROM sessions me WHERE ( me.id = ? ): '8'
Which seems a bit much when all I want to do is update a row. Is there anyway to update a row without having to pull the whole row out of the database first? Something like this is what I am looking for:
my_app->model("DB::Session")->update({done_yn=>'y',end_time=>\'NOW()'},{id=>$id});
Where $id is the WHERE id=? part of the query. Does anyone know how to do this? Thanks!
You can run update on a restricted resultset which only matches this single row:
my_app->model("DB::Session")->search_rs({ id=> 1 })->update({done_yn=>'y',end_time=>\'NOW()'});
I suggest you use a DateTime->now object instead of literal SQL for updating the end_time column because it uses the apps servers date and time instead of the database servers and makes your schema more compatible with different RDBMSes.
Do you have a check if the row was found to prevent an error in case it wasn't?
You might want to use update_or_create instead.
You could use the "columns" attribute:
my $session = my_app->model("DB::Session")->find(1, {columns => "id"});
there is a table named test. in it. there are some columns as this:
001.jpg
...
999.jpg
now i want to use a sql command to add a url before them. as this http://www.example.com/xxx/001.jpg.....is there a way to get this? thank you.
There is two way to accomplish this task. It depends up to you that what you want?
If you want to add a url in the database permanently then you have to use update query with no any where condition, Although if you want to only show your field with this added url you have to use select query.
Please find below the examples for both:
Suppose that your table column name is imageName then UPDATE query will be
UPDATE test SET imageName = CONCAT("http://www.example.com/xxx/", imageName);
And the SELECT query will be
SELECT CONCAT("http://www.example.com/xxx/", imageName) FROM test;
Supposing that your field is called url, a simple UPDATE query will do:
UPDATE test SET url = CONCAT("http://", url);