I'm trying to solve the problem that composite keys in sqlite don't allow autoincrement.
I don't know if it's possible at all, but I was trying to store the last used id in a different table, and use a trigger to assign the next id when inserting a new reccord.
I have to use composite keys, because a single pk wouldn't be unique (because of database merging).
How can I set a field of the row being inserted based on a value in a different table
The query so far is:
CREATE TRIGGER pk BEFORE INSERT ON product_order
BEGIN
UPDATE auto_increment SET value = value + 1 WHERE `table_name` = "product_order";
END
This successfully updates the value. But now I need to assign that new value to the new record. (new.id).
If you use an AFTER INSERT trigger then you can update the newly inserted row, as in the following example.
CREATE TABLE auto_increment (value INT, table_name TEXT);
INSERT INTO auto_increment VALUES (0, 'product_order');
CREATE TABLE product_order (ID1 INT, ID2 INT, name TEXT);
CREATE TRIGGER pk AFTER INSERT ON product_order
BEGIN
UPDATE auto_increment
SET value = value + 1
WHERE table_name = 'product_order';
UPDATE product_order
SET ID2 = (
SELECT value
FROM auto_increment
WHERE table_name = 'product_order')
WHERE ROWID = new.ROWID;
END;
INSERT INTO product_order VALUES (1, NULL, 'a');
INSERT INTO product_order VALUES (2, NULL, 'b');
INSERT INTO product_order VALUES (3, NULL, 'c');
INSERT INTO product_order VALUES (4, NULL, 'd');
SELECT * FROM product_order;
Related
In a sqlite3 database I would like to create a trigger on a view so that I can insert data over the view. Inside the trigger I would like to insert something in the tblmedia table. The id of the inserted row should be now also inserted into the tblbook as id.
In sqlite there are no variables. Otherwise I would store the returning value in the variable and would use it in the second query.
Can this even be achieved in sqlite?
Following my sql schema:
CREATE TABLE tblmedia(
id INTEGER PRIMARY KEY NOT NULL,
title VARCHAR NOT NULL,
raiting INTEGER,
file_name VARCHAR NOT NULL,
media_type TEXT NOT NULL
);
CREATE TABLE tblbook(
id INTEGER PRIMARY KEY NOT NULL,
author VARCHAR,
FOREIGN KEY (id) REFERENCES tblmedia(id) ON DELETE CASCADE
);
CREATE VIEW book AS
SELECT
m.id as id,
m.title as title,
b.author as author,
m.raiting as raiting,
m.file_name as file_name
FROM tblbook b
LEFT JOIN tblmedia m ON m.id = b.id;
CREATE TRIGGER insert_book
INSTEAD OF INSERT ON book
BEGIN
INSERT INTO tblmedia(title, raiting, file_name)
VALUES(new.title, new.raiting, new.file_name);
INSERT INTO tblbook(id, author)
VALUES (xx, new.author); -- xx should be the id from the previous insert
END
It give me error example image at below:
Trigger code:
CREATE OR REPLACE TRIGGER InsertNewStaffs
BEFORE INSERT ON Staffs
FOR EACH ROW
ENABLE
DECLARE
v_user varchar(255);
v_date varchar(255);
v_Staffs_ID Staffs.Staffs_ID%TYPE;
v_Staffs_Name Staffs.Staffs_Name%TYPE;
v_Staffs_Contact_Number Staffs.Staffs_Contact_Number%TYPE;
v_Staffs_Email Staffs.Staffs_Email%TYPE;
v_Orders_ID Staffs.Orders_ID%TYPE;
v_count INTEGER;
BEGIN
SELECT count(*) INTO v_count FROM Staffs
WHERE Staffs_ID = v_Staffs_ID OR
Staffs_Name = v_Staffs_Name OR
Staffs_Contact_Number = v_Staffs_Contact_Number OR
Staffs_Email = v_Staffs_Email;
IF v_count > 0 THEN
RAISE_APPLICATION_ERROR(-20000, 'Oops, some data is already exists. Please try again...');
DBMS_OUTPUT.PUT_LINE('Oops, some data is already exists. Please try again...');
SELECT user, TO_CHAR(sysdate, 'DD/MON/YYYY HH24:MI:SS') INTO v_user, v_date FROM dual;
ELSE
INSERT INTO Staffs(Staffs_ID, Staffs_Name, Staffs_Contact_Number, Staffs_Email, Orders_ID)
VALUES(v_Staffs_ID, v_Staffs_Name, v_Staffs_Contact_Number, v_Staffs_Email, v_Orders_ID);
DBMS_OUTPUT.PUT_LINE('One Row Inserted By ' || v_user || CHR(10));
DBMS_OUTPUT.PUT_LINE('Inserted data at ' || v_date);
INSERT INTO monitorInsertStaffs(user_name, entry_date, operation)
VALUES(v_user, v_date, 'Insert');
END IF;
END;
/
My Table:
CREATE TABLE Staffs(
Staffs_ID char(20) NOT NULL,
Staffs_Name varchar(255) NOT NULL,
Staffs_Contact_Number varchar(50) NOT NULL,
Staffs_Email varchar(255) NOT NULL,
Orders_ID char(20),
PRIMARY KEY (Staffs_ID),
FOREIGN KEY (Orders_ID) REFERENCES Orders(Orders_ID)
);
CREATE TABLE Orders(
Orders_ID char(20) NOT NULL,
Order_Date DATE NOT NULL,
Order_Status varchar(255) NOT NULL,
Order_Quantity int NOT NULL,
Order_TotalAmount NUMERIC(10,2) NOT NULL,
Order_TotalPrice NUMERIC(10,2) NOT NULL,
PRIMARY KEY (Orders_ID),
Pets_Products_ID char(20),
CustomerID char(20),
FOREIGN KEY (Pets_Products_ID) REFERENCES Pets_Products(Pets_Products_ID),
FOREIGN KEY (CustomerID) REFERENCES Customers(CustomerID)
);
I try to insert data and if the data has existed it will show RAISE_APPLICATION_ERROR(-20000, 'Oops, some data is already exists. Please try again...'); but it didn't show the message and also cannot insert data when no exists the data.
I don't know where is error code that I find.
The whole concept is just wrong.
you've based trigger on a table into which you're just inserting a row (staffs)
then you're selecting from the same table (it'll raise the mutating table error if you try to insert more than a single row)
the where clause uses local variables that have no values
insert into staffs cause the same trigger to fire over and over again, until Oracle concludes that that's enough and raises the error
Don't use a trigger. Use UNIQUE constraints:
CREATE TABLE Staffs(
Staffs_ID char(20) NOT NULL,
Staffs_Name varchar(255) NOT NULL,
Staffs_Contact_Number varchar(50) NOT NULL,
Staffs_Email varchar(255) NOT NULL,
Orders_ID char(20),
PRIMARY KEY (Staffs_ID),
UNIQUE (Staffs_Name),
UNIQUE (Staffs_Contact_Number),
UNIQUE (Staffs_Email),
FOREIGN KEY (Orders_ID) REFERENCES Orders(Orders_ID)
);
(However, you should also consider whether your business requirements make sense or if you can have multiple staff members called Jane Smith or if you can have two staff members who share an office with the same telephone number?)
If you want to use a logging table then use an autonomous transaction to just insert into that table:
CREATE OR REPLACE TRIGGER InsertNewStaffs
BEFORE INSERT ON Staffs
FOR EACH ROW
ENABLE
DECLARE
PRAGMA AUTONOMOUS_TRANSACTION;
BEGIN
INSERT INTO monitorInsertStaffs(
user_name, entry_date, operation
) VALUES(
:NEW.Staffs_ID, SYSDATE, 'Insert'
);
COMMIT;
END;
/
db<>fiddle here
I am new to database and have a sqlite database like this:
CREATE TABLE IF NOT EXISTS Tiles (id INTEGER NOT NULL PRIMARY KEY, X INTEGER NOT NULL, Y INTEGER NOT NULL, Zoom INTEGER NOT NULL, Type INTEGER NOT NULL,Date TEXT)
CREATE TABLE IF NOT EXISTS TilesData (id INTEGER NOT NULL PRIMARY KEY CONSTRAINT fk_Tiles_id REFERENCES Tiles(id) ON DELETE CASCADE, Tile BLOB NULL)
If I call the following insert call for the first time:
INSERT INTO Tiles(X, Y, Zoom, Type,Date) VALUES(?, ?, ?, ?,?)
INSERT INTO TilesData(id, Tile) VALUES((SELECT last_insert_rowid()), ?)
What would be the id of Tiles and TilesData?
What's the function of SELECT last_insert_rowid() here?
I built your queries on both SQLFiddle (to easily show you the results) and in a local SQLite instance (to confirm that SQLite (SQL.js) behaves the same as a local instance) using the following script:
CREATE TABLE IF NOT EXISTS Tiles (id INTEGER NOT NULL PRIMARY KEY, X INTEGER NOT NULL, Y INTEGER NOT NULL, Zoom INTEGER NOT NULL, Type INTEGER NOT NULL,Date TEXT);
CREATE TABLE IF NOT EXISTS TilesData (id INTEGER NOT NULL PRIMARY KEY CONSTRAINT fk_Tiles_id REFERENCES Tiles(id) ON DELETE CASCADE, Tile BLOB NULL);
INSERT INTO Tiles(X, Y, Zoom, Type,Date) VALUES(1, 2, 3, 4, 'Date');
INSERT INTO TilesData(id, Tile) VALUES((SELECT last_insert_rowid()), 'Stuff');
select * from Tiles;
select * from TilesData;
In both instances, the id in both tables is 1.
The purpose of select last_insert_rowid() is to determine what the rowid is of the last successful insert. In your example, it is returning the value from the INSERT INTO Tiles query (1) and then assigning that to the id of TilesData.
We can demonstrate this works by also specifying the id in your first insert and seeing that the id of TilesData also matches the forced id.
INSERT INTO Tiles(id, X, Y, Zoom, Type,Date) VALUES(123456, 10, 2, 3, 4, 'Date');
INSERT INTO TilesData(id, Tile) VALUES((SELECT last_insert_rowid()), 'Stuff');
In this example, I'm forcing the id in the Tiles table to be 123456. This value is utilized as the id for the TilesData.
select * from TilesData;
Results in:
id | Tile
--------------
123456 | Stuff
I have created a table with an Id column as varchar(20).
I need a stored procedure which can increment id by 1.
I have tried this:
ALTER PROCEDURE dbo.spInsertCatQuery
(#Users_Id varchar(20),
#Cat_Id varchar(20),
#Query varchar(100),
#Query_Title varchar(50)
)
AS
BEGIN
Declare #Query_Id bigint
SELECT #Query_Id = coalesce((select max(Query_Id) + 1 from tblCatQuery), 1);
INSERT INTO tblCatQuery
VALUES(#Query_Id, #Users_Id, #Cat_Id, #Query_Title, #Query)
END
But it is not working after 10th record.
Change the selection of Query_id from your table to below
SELECT #Query_Id=
coalesce((select max(cast(Query_Id as int)) + 1 from tblCatQuery), 1);
Based on Gordon's comment; my understanding is that since ID is varchar max(id) is not fetching the correct max value but casting it will do so.
For example try this
create table testtab (id varchar(10));
insert into testtab values(2),(200),(53)
If you say below it will return 53
select MAX(id) from testtab
but this one will return 200
select MAX(cast(id as int)) from testtab
Tested in SQL SERVER 2008 R2
You do know your stored procedure has an implicit race condition, don't you?
Between your calculating the new query id and your table insert getting committed, another session can come in, get exactly the same query id, insert it and get committed. Guess what happens when your insert tries to commit? First in wins; the second gets a duplicate key error. Don't ask me how I know this :)
If you really need a text query id, you might try using a computed field, something like this:
create table dbo.tblCatQuery
(
query_id int not null identity(1,1) primary key clustered ,
query_id_text as right('0000000000'+convert(varchar,id),10) ,
user_id varchar(20) not null ,
cat_id varchar(20) not null ,
query varchar(100) not null ,
query_title varchar(50) not null ,
)
Then your stored procedure looks like this:
create procedure dbo.spInsertCatQuery
#Users_Id varchar(20) ,
#Cat_Id varchar(20) ,
#Query varchar(100) ,
#Query_Title varchar(50) ,
#Query_ID varchar(10) output
AS
insert dbo.tblCatQuery ( user_id , cat_id , query_title , query )
VALUES ( #Users_Id , #Cat_Id , #Query_Title , #Query )
-- give the caller back the id of the row just inserted
set #Query_ID = ##SCOPE_IDENTITY
-- for redundancy, hand it back as the SP's return code, too
return #Query_ID
GO
It sounds like your application needs a string for the ID field, yet in the database you want it ID to behave as an auto-incrementing integer field.
Consider using an integer in the database, and when you retrieve the value and need to use it as as string, at that point convert the value to a string, either in your query or in your application.
This will solve your problem.
You must seriously review your design. I shall suggest something like this.
CREATE TABLE tblCatQuery(QueryId int NOT NULL PRIMARY KEY IDENTITY(1, 1),
UserId int NOT NULL REFERENCES tblUsers(UserId),
CatId int NOT NULL REFERENCES tblCat(CatId),
Query varchar(100), Query_Title varchar(50))
CREATE TABLE tblUsers(UserId int NOT NULL PRIMARY KEY IDENTITY(1, 1), ....
CREATE TABLE tblCat(CatId int NOT NULL PRIMARY KEY IDENTITY(1, 1), ....
CREATEPROCEDURE dbo.spInsertCatQuery
(
#Users_Id int,
#Cat_Id int,
#Query varchar(100),
#Query_Title varchar(50)
)
AS
BEGIN
INSERT INTO tblCatQuery(Users_Id, Cat_Id, Query_Title, Query)
VALUES( Users_Id, Cat_Id, Query_Title, Query)
END
I have 2 tables
CREATE TABLE PODRAS_MS.tbl_FieldWorkers
(
[FWInsOnServerID] INT NOT NULL IDENTITY(1,1),
[BaseStationID] INT NOT NULL,
[RefID] INT NOT NULL,
[DisSubInsID] INT NOT NULL,
[FieldWorkerID] CHAR(7) NOT NULL,
[LastRecDate] DATETIME NOT NULL,
)
ALTER TABLE PODRAS_MS.tbl_FieldWorkers ADD CONSTRAINT PK_FieldWorkers_FWInsOnServerID PRIMARY KEY([FWInsOnServerID])
ALTER TABLE PODRAS_MS.tbl_FieldWorkers ADD CONSTRAINT FK_FieldWorkers_DisSubInsID FOREIGN KEY([DisSubInsID]) REFERENCES PODRAS_MS.tbl_DisasterSubInstances([SubInsID]) ON UPDATE CASCADE ON DELETE NO ACTION
ALTER TABLE PODRAS_MS.tbl_FieldWorkers ADD CONSTRAINT FK_FieldWorkers_BaseStationID FOREIGN KEY([BaseStationID]) REFERENCES PODRAS_MS.tbl_BaseStations([BaseStationID]) ON UPDATE CASCADE ON DELETE NO ACTION
ALTER TABLE PODRAS_MS.tbl_FieldWorkers ADD CONSTRAINT DF_FieldWorkers_LastRecDate DEFAULT(GETDATE()) FOR [LastRecDate]
GO
CREATE TABLE PODRAS_MS.tbl_FieldWorkerNodeGPSLocations
(
[FWNStatID] INT NOT NULL IDENTITY(1,1),
[FWInsOnServerID] INT NOT NULL,
[Latitude] DECIMAL(20,17) NOT NULL,
[Longitude] DECIMAL(20,17) NOT NULL,
[UpdateOn] DATETIME NOT NULL,
)
ALTER TABLE PODRAS_MS.tbl_FieldWorkerNodeGPSLocations ADD CONSTRAINT PK_FieldWorkerNodeGPSLocations_FWNStatID PRIMARY KEY([FWNStatID])
ALTER TABLE PODRAS_MS.tbl_FieldWorkerNodeGPSLocations ADD CONSTRAINT FK_FieldWorkerNodeGPSLocations_FWInsOnServerID FOREIGN KEY([FWInsOnServerID]) REFERENCES PODRAS_MS.tbl_FieldWorkers([FWInsOnServerID]) ON UPDATE CASCADE ON DELETE NO ACTION
ALTER TABLE PODRAS_MS.tbl_FieldWorkerNodeGPSLocations ADD CONSTRAINT DK_FieldWorkerNodeGPSLocations_UpdateOn DEFAULT(GETDATE()) FOR [UpdateOn]
GO
Both tables are updated through a webservice in the 1st table all the fields can be inserted through the web service but in the second table only data for [Latitude],[Longitude],[UpdateOn] fields comes through the webservice.so my problem is how can i insert the values to [FWInsOnServerID] field since its not comes through the webservice and its a reference for the 1st table???
If I understand you correctly, the insert in the second table is dependant on the result of the insert in your first table?
In this case, you could simply return the generted ID of the first table and use that result to insert into the second table.
Something like (if you're using Stored Procedures).
SELECT SCOPE_IDENTITY()
at the end of your stored procedure. And then in your .NET code which handles the database code, use that number to do the second insert.
You could do it all in a single stored procedure like this:
CREATE PROCEDURE PODRAS_MS.insert_FieldWorker()
#BaseStationID INT,
#RefID INT,
#DisSubInsID INT,
#FieldWorkerID CHAR(7),
#Latitude DECIMAL(20,17),
#Longitude DECIMAL(20,17)
AS
BEGIN
INSERT INTO
PODRAS_MS.tbl_FieldWorkers
([BaseStationID], [RefID], [DisSubInsID], [FieldWorkerID])
VALUES (#BaseStationID, #RefID, #DisSubInsID, #FieldWorkerID)
DECLARE #FWInsOnServerID INT
SELECT #FWInsOnServerID = SCOPE_IDENTITY()
INSERT INTO PODRAS_MS.tbl_FieldWorkerNodeGPSLocations
([FWInsOnServerID], [Latitude], [Longitude])
VALUES (#FWInsOnServerID, #Latitude, #Longitude)
END
You could then select the records from the same stored procedure, but it is more common to separate this out into another stored proc.
EDIT: use an output parameter
CREATE PROCEDURE PODRAS_MS.insert_FieldWorker()
#BaseStationID INT,
#RefID INT,
#DisSubInsID INT,
#FieldWorkerID CHAR(7),
#FWInsOnServerID INT output
AS
BEGIN
INSERT INTO
PODRAS_MS.tbl_FieldWorkers
([BaseStationID], [RefID], [DisSubInsID], [FieldWorkerID])
VALUES (#BaseStationID, #RefID, #DisSubInsID, #FieldWorkerID)
SELECT #FWInsOnServerID = SCOPE_IDENTITY()
END