I wrote a trigger something like this:
CREATE TRIGGER `update_after_itemPresent` AFTER INSERT ON `bus_repair`
FOR EACH ROW begin
IF NEW.unit <> `item_present`.`unit` THEN
update item_present
set unit = unit-new.unit
where item_present.item_group_id = new.item_group_id;
END IF;
end
But when I insert new row in bus_repair table it gives an error that:
unknown table item_present in field list
Any idea how to fix this?
Move your UPDATE item_preset statement above the IF and the IF inside the UPDATE or rephrase as a condition. You need to UPDATE or SELECT the table item_present first.
Related
I have an after insert trigger that is supposed to update the field total in my table "test" where the id_cart is equal to new.id_cart. However my trigger is updating every single row in the table not only the one desired. I would like to know how can I modify my trigger so it only updates the row that I want.
This is my trigger.
CREATE DEFINER=`root`#`localhost` TRIGGER `update_total_test`
AFTER INSERT ON `test_product_quantity_cart`
FOR EACH ROW BEGIN
UPDATE test set total= (select sum(price_product) from test_product_quantity_cart where id_cart=new.id_cart);
END
So if the new row inserted in table "test_product_quantity_cart" has an new.id_cart=1, then only the row in table "test" with id_cart=1 should be uptated.
I think I am missing a "where" clause to indicate the update statement which rows it is suppossed to upate. However I do not know how to add that clause.
Thank you!
CREATE DEFINER=`root`#`localhost` TRIGGER `update_total_test`
AFTER INSERT ON `test_product_quantity_cart`
FOR EACH ROW
UPDATE test
JOIN ( SELECT id_cart, SUM(price_product) total
FROM test_product_quantity_cart
WHERE id_cart=NEW.id_cart ) value_for_update USING (id_cart)
SET test.total = value_for_update.total;
I have a table which contain some fields(id,code,name,...), when I want to insert new record the code field should be like (ABC-001) and next record should be like (ABC-002) and so on.
I want to write a MYSQL procedure for this but I don't know how, any body has any idea? thanks in advance
First User Insert Query like:
Insert Into YourTable Values(..,'ABC',...);
Now write trigger after update which set Code value in expected format:
CREATE TRIGGER TriggerNmae AFTER INSERT ON YourTable
FOR EACH ROW
Begin
UPDATE YourTable
SET code = concat(code,'-',LPAD(NEW.id,3,'0'));
WHERE id = New.id ;
END;
On MySQL 5.5, I am trying to write a trigger to do the following:
Checks a condition for the insert (is group_id between 8-20?)
If the condition is true, then update the user with the same user_id on another table, called phpbb_users.
The update on this other table is to set user_rank to NEW.group_id from the insert on the table that has the trigger.
Else, do nothing.
Not experienced at all, and stuck. It's not working when I run the query. Here is what I've got so far.
DELIMITER $$
CREATE OR REPLACE TRIGGER upd_rank AFTER INSERT ON `phpbb_user_group`
FOR EACH ROW BEGIN
IF (NEW.group_id BETWEEN 8 AND 20) THEN
UPDATE phpbb_users
SET user_rank=NEW.group_id
WHERE user_id=NEW.user_id;
ELSE
UPDATE phpbb_users
SET user_rank='0'
WHERE user_id=NEW.user_id;
END IF;
END$$;
DELIMITER;
(Note, the "else" clause is unnecessary really - happy for any suggestions for improvement of this code!)
if you only want to get rid of the else try
CREATE TRIGGER upd_rank AFTER INSERT ON `phpbb_user_group`
FOR EACH ROW
UPDATE phpbb_users
SET user_rank=IF(NEW.group_id BETWEEN 8 AND 20,NEW.group_id,"0")
WHERE user_id=NEW.user_id;
I have the following trigger:
CREATE TRIGGER sum
AFTER INSERT
ON news
FOR EACH ROW
UPDATE news SET NEW.sum = (NEW.int_views + NEW.ext_views)/NEW.pageviews
It sums the int_views and ext_views column of a table and divides them by the total pageviews.
Whenever I try to add a new row to news, I get the following error:
ERROR 1442 (HY000) at line 3: Can't update table 'news' in stored function/trigger because it is already used by statement which invoked this stored function/trigger.
The trigger seems pretty simple to me. Is there a reason why the trigger fails to run?
The symptom is, that you are running an UPDATE (for all rows) inside a INSERT trigger - both modify the table, which is not allowed.
That said, if I guess the intention of your trigger correctly, you do not want to update all rows, but only the newly inserted row. You can achieve that easily with
CREATE TRIGGER sum
BEFORE INSERT
ON news
FOR EACH ROW
SET NEW.sum = (NEW.int_views + NEW.ext_views)/NEW.pageviews
Mind that this is a BEFORE INSERT trigger, as you want to change the row before it is written to the table.
If you try to update/insert on the same table that cause trigger to fire do not use the common sql command like
-> UPDATE TABLE_NAME SET COLUMN_NAME = VALUE WHERE CONDITION_LIST;
-> INSERT INTO TABLE_NAME VALUES("VALUE1","VALUE2");
This will not work. Only use set to assign the value of the column you update.
Example:
CREATE TRIGGER trigger_name BEFORE/AFTER INSERT/UPDATE ON table_name
FOR EACH ROW
SET NEW.COLUMN_NAME = "VALUE";
I was in a similar condition where I had to run two triggers:
UPDATE 3 fields on INSERTing a new ROW
UPDATE 3 fields on UPDATEing a ROW
After lot of efforts, I was finally able to write the TRIGGER in following way:
FOR updating values on INSERT
CREATE TRIGGER `INSERT_DISCOUNT_SERVICES` BEFORE INSERT ON `services`
FOR EACH ROW SET
NEW.discount_5_rate = (NEW.ndis_rate*0.05),
NEW.discount_10_rate=(NEW.ndis_rate*0.10),
NEW.discount_15_rate=(NEW.ndis_rate*0.15)
Similarly
FOR updating values on UPDATE
CREATE TRIGGER `UPDATE_DISCOUNTS_SERVICES` BEFORE UPDATE ON `services`
FOR EACH ROW SET
NEW.discount_5_rate = (NEW.ndis_rate*0.05),
NEW.discount_10_rate=(NEW.ndis_rate*0.10),
NEW.discount_15_rate=(NEW.ndis_rate*0.15)
Hello, every one :)!
I'll try and keep this as simple as possible, basically, I have one table that references itself via a parent_id column. Each row in the table can have a parent and can keep count of how many children it has via the count column. So essentially what I'm trying to do is have the triggers update each parent row's count column when necessary
The problem is that the update trigger gets called when the update operation in the insert trigger gets called. Then I get:
"General error: 1442 Can't update table 'term_taxonomies' in stored function/trigger because it is already used by statement which invoked this stored function/trigger".
Any ideas?
Actual code:
TRIGGER `dbname`.`ai_term_taxonomies`
AFTER INSERT ON `dbname`.`term_taxonomies`
FOR EACH ROW
BEGIN
IF NEW.parent_id NOT 0 THEN
UPDATE term_taxonomies as termTax SET assocItemCount = (assocItemCount + 1)
WHERE termTax.term_taxonomy_id = NEW.parent_id;
END IF;
END$$
CREATE
TRIGGER `dbname`.`au_term_taxonomies`
AFTER UPDATE ON `dbname`.`term_taxonomies`
FOR EACH ROW
BEGIN
IF NEW.parent_id NOT OLD.parent_id THEN
IF NEW.parent_id NOT 0 THEN
UPDATE term_taxonomies as termTax SET assocItemCount = (assocItemCount + 1)
WHERE termTax.term_taxonomy_id = NEW.parent_id;
END IF;
IF OLD.parent_id NOT 0 THEN
UPDATE term_taxonomies as termTax SET assocItemCount = (assocItemCount - 1)
WHERE termTax.term_taxonomy_id = OLD.parent_id;
END IF;
END IF;
END$$
All mysql triggers execute in the same transaction as the triggering statement.
You want to update using the SET NEW.assocItemCount syntax as opposed to performing an UPDATE statement on the underlying table.
Edit: However, in your case this is not possible because you are updating a different row in the same table, the hardest thing to do in a mysql trigger. Sorry.
You will have to change your schema. Take assocItemCount out of your table, create a new table holding just term_taxonomy_id and assocItemCount, and update that using an UPDATE statement from your query. It is also possible to use a view joining these two tables to hide this detail if a query needs to use your original schema.
Alternatively, if you did not have assocItemCount in your database at all, you would still be able to compute it in any queries, and your database would be better normalized than it is now.