Trigger to insert values from another table - Mysql - mysql

I did this to trigger when the temperature is higher or lower than the parameter set off an alarm. Ie automatically populates the fields of the table alarm.
Now I created a new row in the table alarms, the idRegisto which is foreign key, now I want that id be completed in accordance with the idRegisto other corresponding table.
Does anyone can help me please?
If you are not understanding the question I will try to clarify further.
Thank you.
------------TRIGGER-------------------
DELIMITER $$
create TRIGGER alerta
BEFORE INSERT ON registos
FOR EACH ROW
begin
Set #tempmax=0;
Set #tempmin=0;
Set #hummax=0;
select lim_inf_temp, lim_sup_temp into #tempmin, #tempmax from sensores where idSensor=NEW.idSensor;
Set #maxidAlarme=0;
if (CAST(NEW.Temperatura AS UNSIGNED)<#tempmin) then
SELECT MAX(idAlarme) into #maxidAlarme FROM alarmes;
SET #maxidAlarme=#maxidAlarme+1;
INSERT INTO alarmes(idAlarme,descricao_alarme) VALUES (#maxidAlarme,"high-temperature");
INSERT INTO sensores_tem_alarmes(idSensor,idAlarme,dataAlarme) VALUES (NEW.idSensor,#maxidAlarme,NOW());
end if;
if (CAST(NEW.Temperatura AS UNSIGNED)>#tempmax) then
SELECT MAX(idAlarme) into #maxidAlarme FROM alarmes;
SET #maxidAlarme=#maxidAlarme+1;
INSERT INTO alarmes(idAlarme,descricao_alarme) VALUES (#maxidAlarme,"lower temperature");
INSERT INTO sensores_tem_alarmes(idSensor,idAlarme,dataAlarme) VALUES (NEW.idSensor,#maxidAlarme,NOW());
end if;
DELIMITER ;
------------ER------------------------

You can use an "after insert trigger"
AFTER INSERT ON registos
And take the "New.IdRegistro" to use as foreign key when populating the alarmes table.
//EDIT:
using your code:
AFTER INSERT ON registos
FOR EACH ROW
begin
Set #tempmax=0;
Set #tempmin=0;
Set #hummax=0;
...
INSERT INTO alarmes(idAlarme,descricao_alarme,idRegistro) VALUES (#maxidAlarme,"lower temperature",New.IdRegistro);
INSERT INTO sensores_tem_alarmes(idSensor,idAlarme,dataAlarme) VALUES (NEW.idSensor,#maxidAlarme,NOW());
...
I assume here that IdRegistro is a primary key (that will be autogenarated by your application or via autoincrement) of the registro table.
Register->if value higher/lower threshold -> trigger alarm -> insert sensores_tem_alarmes

Related

Increment a number field via a trigger INSERT in MySQL

I'm building a data versioning system, and I need to increment a version number each time a new row is added to the version table, but it increments once and then stops:
DELIMITER |
CREATE TRIGGER trigger2 AFTER UPDATE ON something
FOR EACH ROW
BEGIN
IF NEW.updated_at <> OLD.updated_at THEN
INSERT INTO versions_something (
`id`,
`some_id`,
`version`,
`title`,
`description`,
`created_at`,
`updated_at`
) VALUES (
null,
NEW.id,
1,
NEW.title,
NEW.description,
NOW(),
NOW()
);
END IF;
UPDATE
versions_something
SET
version = (SELECT MAX(version)) + 1
WHERE versions_something.id = LAST_INSERT_ID();
END;
|
DELIMITER ;
I've tried putting the UPDATE into a separate trigger (AFTER INSERT ON versions_something ...), but MySQL complains that it's clashing with the trigger before it.
I've tried the UPDATE on its own, using the last ID in the table and it works each time, so I have no idea what's happening.

MySQL - Insert Into 2 Tables on 1 Procedure

I need to create a procedure for inserting records into 2 tables, but on the second table, I want to insert the last ID that was inserted on the first table. Could anyone help me with this?
This is my query
DELIMITER //
DROP PROCEDURE IF EXISTS ROOM_FEATURE_INSERT;
CREATE PROCEDURE ROOM_FEATURE_INSERT (propID INT, featID INT, featNme VARCHAR(50))
BEGIN
-- BEGIN CHECK
IF NOT EXISTS
(
SELECT rFeatureName FROM COMPANY_T3s71.PROPERTY_RFEATURE PRFE
INNER JOIN COMPANY_T3s71.ROOM_FEATURE RFEA ON PRFE.rFeatureID=RFEA.rFeatureID
WHERE BINARY rFeatureName = featNme AND propertyID = propID
)
AND
(
SELECT rFeatureName FROM COMPANY_T3s71.ROOM_VIEW
WHERE BINARY rFeatureName = featNme
)
THEN
-- IF NOT EXISTS INSERT INTO 1st TABLE
INSERT INTO COMPANY_T3s71.ROOM_FEATURE (rFeatureName) VALUES (featNme);
END IF;
-- END CHECK
-- BEGIN CHECK 2nd TABLE
IF NOT EXISTS
(
SELECT propertyID, rFeatureID FROM COMPANY_T3s71.PROPERTY_RFEATURE
WHERE rFeatureID = featID AND propertyID = propID
)
THEN
-- IF NOT EXISTS INSERT INTO 2nd TABLE
INSERT INTO COMPANY_T3s71.PROPERTY_RFEATURE (propertyID, rFeatureID) VALUES (propID, featID);
END IF;
-- END CHECK 2nd TABLE
END
DELIMITER ;
How do we pass the featID param, when we just inserted it on the first INSERT query?
Thank you before hand.
Use SET featID = LAST_INSERT_ID(); after the first query and then use the variable
INSERT INTO COMPANY_T3s71.ROOM_FEATURE (rFeatureName) VALUES (featNme);
SET featID = LAST_INSERT_ID();
However, if the data is not insert at anytime then you have to make query in the if block to set the value for featID.

IF NOT EXISTS in mysql showing syntax error

I am trying to convert this tsql to mysql but showing error need help
CREATE PROCEDURE FormAdd
#formName varchar(MAX)
AS
IF NOT EXISTS(SELECT * FROM tbl_Form WHERE formName=#formName)
BEGIN
INSERT INTO tbl_Form
(formName)
VALUES
(#formName)
SELECT ##identity
END
ELSE
BEGIN
SELECT '-1'
END
mysql
CREATE PROCEDURE FormAdd
(p_formName varchar(500) )
begin
INSERT INTO tbl_Form (formName)
VALUES (p_formName)
where NOT EXISTS(SELECT * FROM tbl_Form WHERE formName=p_formName) ;
SELECT Last_insert_id() as returnvalue ;
SELECT '-1' ;
end
Your attempt was syntactically invalid because logically, an INSERT statement cannot contain a WHERE clause since it does not act on existing rows.
If the purpose is to insert only if the value for p_formname is not already present, then an appropriate step would be to define a unique index on that column first. Then, construct your procedure to attempt the insert and inspect the ROW_COUNT() value to see if one was inserted and act accordingly, returning -1 if not to adapt your existing T-SQL procedure.
First create the unique index on p_formname:
ALTER TABLE tbl_Form ADD UNIQUE KEY `idx_formName` (`formName`);
Then your procedure should use INSERT INTO...ON DUPLICATE KEY UPDATE to attempt to insert the row. Per the documentation, the value of ROW_COUNT() will be 0 if a new row was not inserted or 1 if it was.
CREATE PROCEDURE FormAdd (p_formName varchar(500))
BEGIN
/* Attempt the insert, overwrite with the same value if necessary */
INSERT INTO tbl_Form (formName) VALUES (p_formName) ON DUPLICATE KEY UPDATE formName = p_formName;
/* Return the LAST_INSERT_ID() for a new row and -1 otherwise */
SELECT
CASE
WHEN ROW_COUNT() = 1 THEN LAST_INSERT_ID()
ELSE -1
END AS returnValue;
END

MYSQL Insert values from another table - trigger

I have these tables in my database:
I want to add the registod and alarmes table one idRegisto .
The alarm table is populated automatically by a trigger. I would like to connect the two tables and the table alarmes populated idRegistos automatically by a trigger with the values โ€‹โ€‹of table records.
Does anyone can help me please.
I hope I have explained well my doubts
Thank you
My Trigger that populated table alarmes
DELIMITER $$
create TRIGGER alerta
BEFORE INSERT ON registos
FOR EACH ROW
begin
Set #comp=0;
Set #tempmax=0;
Set #tempmin=0;
Set #hummax=0;
Set #hummin=0;
Set #orvalho=0;
select lim_inf_temp, lim_sup_temp, lim_sup_humid, lim_inf_humid, lim_pt_orvalho into #tempmin, #tempmax, #hummax, #hummin, #orvalho from sensores where idSensor=NEW.idSensor;
Set #maxidAlarme=0;
if (CAST(NEW.Temperatura AS UNSIGNED)<#tempmin) then
SELECT MAX(idAlarme) into #maxidAlarme FROM alarmes;
SET #maxidAlarme=#maxidAlarme+1;
INSERT INTO alarmes(idAlarme,descricao_alarme) VALUES (#maxidAlarme,"ERROR");
end if;
end $$;
DELIMITER ;
In alarm table, do you want to use the same newly generated idRegisto of registos table? - Ravinder
Yes. This is what i want. โ€“ user3320956
To insert the same newly generated idRegisto field value in alarm table,
Change part of your trigger body as below:
if ( CAST( NEW.Temperatura AS UNSIGNED ) < #tempmin ) then
SELECT MAX( idAlarme ) into #maxidAlarme FROM alarmes;
SET #maxidAlarme := #maxidAlarme + 1;
SET #auto_idRegisto := ( SELECT AUTO_INCREMENT
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = 'registos'
AND TABLE_SCHEMA = DATABASE() );
INSERT INTO alarmes( idAlarme, descricao_alarme, idRegisto )
VALUES ( #maxidAlarme, "ERROR", #auto_idRegisto );
end if;

mysql trigger error with 2 conditions

I want to add an after insert trigger which will do the following.
The first IF condition works normally, but when it comes to the second everything stops.
Any ideas?
USE `Syslog`;
DELIMITER $$
CREATE TRIGGER `SystemEventsR_AINS` AFTER INSERT ON SystemEventsR FOR EACH ROW
IF
(exists
(select syslogtag from SystemEventsRcounter where syslogtag=
new.syslogtag)
AND
(select simpledate from SystemEventsRcounter
where syslogtag=new.syslogtag)=new.simpledate)
THEN
UPDATE SystemEventsRcounter
SET records=records+1
WHERE SystemEventsRcounter.syslogtag=new.syslogtag;
ELSE INSERT SystemEventsRcounter (simpledate, syslogtag, records) values (new.simpledate,new.syslogtag,1);
END IF
UPDATED:
What you need is INSERT INTO ... ON DUPLICATE KEY.
CREATE TRIGGER `SystemEventsR_AINS`
AFTER INSERT ON SystemEventsR
FOR EACH ROW
INSERT INTO SystemEventsRcounter (simpledate, syslogtag, records)
VALUES (NEW.simpledate, NEW.syslogtag, 1)
ON DUPLICATE KEY UPDATE records = records + 1;
In order for it to work you need to create a unique composite index on (simpledate, syslogtag)
CREATE UNIQUE INDEX idx_u_simpledate_syslogtag
ON SystemEventsRcounter (simpledate, syslogtag);
Here is SQLFiddle demo.
If you wanted it your way then it might look like
DELIMITER $$
CREATE TRIGGER `SystemEventsR_AINS`
AFTER INSERT ON SystemEventsR
FOR EACH ROW
BEGIN
IF (
SELECT COUNT(*) simpledate
FROM SystemEventsRcounter
WHERE syslogtag = NEW.syslogtag
AND simpledate = NEW.simpledate
) > 0 THEN
UPDATE SystemEventsRcounter
SET records = records + 1
WHERE SystemEventsRcounter.syslogtag = NEW.syslogtag;
ELSE
INSERT INTO SystemEventsRcounter (simpledate, syslogtag, records)
VALUES (NEW.simpledate, NEW.syslogtag, 1);
END IF;
END$$
DELIMITER ;
Here is SQLFiddle demo.