I am trying to create a simple SQLite database that will allow me to store email addresses and timestamps. I have created the table like this:
$sql =<<<EOF
CREATE TABLE ENTRIES
(ID INT PRIMARY KEY NOT NULL,
EMAIL EMAIL NOT NULL,
TIMESTAMP DATETIME DEFAULT CURRENT_TIMESTAMP);
EOF;
And I am trying to insert an email like this:
$sql =<<<EOF
INSERT INTO ENTRIES (EMAIL)
VALUES (test#test.com);
EOF;
I am getting an error
NOT NULL constraint failed: ENTRIES.ID
I am assuming this is to do with the ID and autoincrement? I have read the docs and it advises against using autoincrement. Where am I going wrong?
The docs say:
If a table contains a column of type INTEGER PRIMARY KEY, then that column becomes an alias for the ROWID.
And because it becomes an alias for the ROWID, it's not necessary to explicitly specify a value.
You have INT PRIMARY KEY, not INTEGER PRIMARY KEY. If you change it to INTEGER PRIMARY KEY, it works the way you expect.
Related
I have a primary key column in my SQL table in PostgreSQL named "id". It is a "bigseries" column. I want to convert the column to a "UUID" column. It entered the below command in the terminal:
alter table people alter column id uuid;
and
alter table people alter column id uuid using (uuid_generate_v4());
but neither of them worked.
In both tries I got the error message
ERROR: syntax error at or near "uuid"
LINE 1: alter table people alter column id uuid using (uuid_generate...
What is the correct syntax?
First of all uuid_generate_v4() is a function which is provided by an extension called uuid-ossp. You should have install that extension by using;
CREATE EXTENSION uuid-ossp;
Postgresql 13 introduced a new function which does basically the same without installing extension. The function is called gen_random_uuid()
Suppose that we have a table like the one below;
CREATE TABLE people (
id bigserial primary key,
data text
);
The bigserial is not a real type. It's a macro which basically creates bigint column with default value and a sequence. The default value is next value of that sequence.
For your use case, to change data type, you first should drop the old default value. Then, alter the type and finally add new default value expression. Here is the sample:
ALTER TABLE people
ALTER id DROP DEFAULT,
ALTER id TYPE uuid using (gen_random_uuid() /* or uuid_generate_v4() */ ),
ALTER id SET DEFAULT gen_random_uuid() /* or uuid_generate_v4() */ ;
CREATE TABLE IF NOT EXISTS people (
id uuid NOT NULL CONSTRAINT people_pkey PRIMARY KEY,
address varchar,
city varchar(255),
country varchar(255),
email varchar(255),
phone varchar(255)
);
This is the correct syntax to create table in postgres SQL, it's better to do these constraints at beginning to avoid any error.
For using alter command you would do the following:
ALTER TABLE customer ADD COLUMN cid uuid PRIMARY KEY;
Most of errors that you could find while writing command either lower case or undefined correct the table name or column.
I would like to do analysis of what codes appear in multiple tables under certains conditions. However I don't think the database schema suits the task very well but maybe there's something I don't know about that can help me. Here's a simplified schema:
CREATE TABLE "batchDescription" (
id INTEGER NOT NULL,
name TEXT NOT NULL UNIQUE,
PRIMARY KEY (id)
);
CREATE TABLE "simulationDetails" (
id INTEGER NOT NULL,
ko_index_id INTEGER NOT NULL,
batch_description_id INTEGER NOT NULL,
data1 REAL NOT NULL,
data2 INTEGER NOT NULL,
PRIMARY KEY (id)
FOREIGN KEY(ko_index_id) REFERENCES "koIndex" (id)
FOREIGN KEY(batch_description_id) REFERENCES "batchDescription" (id)
);
CREATE TABLE "koIndex" (
id INTEGER NOT NULL,
number_of_kos INTEGER NOT NULL,
PRIMARY KEY (id)
);
CREATE TABLE "1kos" (
ko_index_id INTEGER NOT NULL,
ko1 INTEGER NOT NULL,
PRIMARY KEY (ko_index_id)
FOREIGN KEY(ko_index_id) REFERENCES "koIndex" (id)
);
CREATE TABLE "2kos" (
ko_index_id INTEGER NOT NULL,
ko1 INTEGER NOT NULL,
ko2 INTEGER NOT NULL,
PRIMARY KEY (ko_index_id)
FOREIGN KEY(ko_index_id) REFERENCES "koIndex" (id)
);
CREATE TABLE "3kos" (
ko_index_id INTEGER NOT NULL,
ko1 INTEGER NOT NULL,
ko2 INTEGER NOT NULL,
ko3 INTEGER NOT NULL,
PRIMARY KEY (ko_index_id)
FOREIGN KEY(ko_index_id) REFERENCES "koIndex" (id)
);
This goes up to table "525kos" which has ko1 to ko525 in it - ko1 to ko525 are IDs that are primary keys in a table not shown here. I want to do an analysis of how often certain IDs are present under certain conditions. Here is a simple example to illustrate:
I would like to like to count the amount of times a certain ID (let's say 127) (in any koX column) in the "13kos" table occurs when simulationDetails.data1 not equal to 0. I would do this on a database called ko.db from the bash command line like:
for ko_idx in {1..13}; do sqlite3 ko.db "select count(ko${ko_idx}) from '13kos' where ko${ko_idx} = 127 and ko_index_id in (select ko_index_id from simulationDetails where data1 != 0);"; done
Already this is slow and inefficient but is simple compared to what I would like to do. What if I wanted to do an analysis of all the IDs in all possible columns in all "Xkos" tables and compare them to where data1 is equal and not equal to zero?
Can anybody direct me to a better way of doing this or is the schema design just not very good for this kind of analysis and I'll have to give up?
EDIT: Thought I'd add a bit of extra detailto avoid confusion. I suspect that a good way to achieve want I want would be to somehow combine all the "Xkos" tables into one temporary table and then search for certain IDs from that table. How would I combine all 525 ko tables without writing out each table name?
How would I combine all 525 ko tables without writing out each table
name?
Create a table with the same number of columns as the largest table (the table into which you merge) allowing nulls.
query the sqlite_master table using something like :-
SELECT * from sqlite_master WHERE name LIKE '%kos%' AND type = 'table'
Loop through the extracted table names building an INSERT SELECT for each table that will insert the rows from the tables into the table created in 1.
See 2. INSERT INTO table SELECT ...; especially in regard to handling missing columns.
All done, the table created in 1 will be populated accordingly.
I've tried to search but nothing works, and I don't know what to do.
There's a table with two foreign keys, one of which can be null. According to what I've searched, it's perfectly fine to have null foreign keys. But no matter what, when I try to insert a null in that value, it fails. It says:
*Cause: A foreign key value has no matching primary key value.
*Action: Delete the foreign key or add a matching primary key.
Here is the code of the table. The FK that I want to be null is idPedido
CREATE TABLE PAGOS(
fechaLimite DATE,
cuantia NUMBER NOT NULL,
fechaInicio DATE DEFAULT SYSDATE,
fechaLiquidacion DATE,
idPago VARCHAR(8) NOT NULL,
dni VARCHAR(14) NOT NULL,
tipoPago VARCHAR(7) DEFAULT 'OTRO' CHECK(tipoPAGO IN('MENSUAL','PEDIDO','OTRO')),
idPedido VARCHAR2(10),
PRIMARY KEY(idPago),
FOREIGN KEY(dni) REFERENCES MIEMBROS ON DELETE SET NULL,
FOREIGN KEY(idPedido) REFERENCES PEDIDOS ON DELETE SET NULL
);
There are some triggers and such to add sequences for the idPago value.
Here is the code of the procedure that creates a new item to the table:
create or replace PROCEDURE CREAR_PAGO(
new_fechaLimite IN PAGOS.fechaLimite%TYPE ,
new_cuantia IN PAGOS.cuantia%TYPE,
new_fechaInicio IN PAGOS.fechaInicio%TYPE,
new_fechaLiquidacion IN PAGOS.fechaLiquidacion%TYPE,
new_dni IN PAGOS.dni%TYPE,
new_tipoPago IN PAGOS.tipoPago%TYPE,
new_idPedido IN PAGOS.idPedido%TYPE
)
IS
BEGIN
INSERT INTO PAGOS(fechaLimite,cuantia,fechaInicio,fechaLiquidacion,dni,tipoPago,idPedido) VALUES(new_fechaLimite,new_cuantia,new_fechaInicio,new_fechaLiquidacion,new_dni,new_tipoPago,new_idPedido);
END CREAR_PAGO;
And here is me trying to insert a new element:
execute CREAR_PAGO('01012020',40,'01012010',null,49035480D,null,null);
I've already tried to put both "NULL" and "DEFAULT NULL" in the table code after idPedido's type and nothing works
Please I need help
It looks like the primary key for your table is idPago, but I don't see it in your insert statement. If that is the case, it would appear that your issue is trying to add a record with no primary key...not that the foreign key is null.
I have a table with the following definition:
CREATE TABLE url_tracker (
id int not null identity(1, 1),
active bit not null,
install_date int not null,
partner_url nvarchar(512) not null,
local_url nvarchar(512) not null,
public_url nvarchar(512) not null,
primary key(id)
);
And I have a requirement that these three URLs always be unique - any individual URL can appear many times, but the combination of the three must be unique (for a given day).
Initially I thought I could do this:
CREATE UNIQUE INDEX uniques ON url_tracker
(install_date, partner_url, local_url, public_url);
However this gives me back the warning:
Warning! The maximum key length is 900 bytes. The index 'uniques' has maximum
length of 3076 bytes. For some combination of large values, the insert/update
operation will fail.
Digging around I learned about the INCLUDE argument to CREATE INDEX, but according to this question converting the command to use INCLUDE will not enforce uniqueness on the URLs.
CREATE UNIQUE INDEX uniques ON url_tracker (install_date)
INCLUDE (partner_url, local_url, public_url);
How can I enforce uniqueness on several relatively large nvarchar fields?
Resolution
So from the comments and answers and more research I'm concluding I can do this:
CREATE TABLE url_tracker (
id int not null identity(1, 1),
active bit not null,
install_date int not null,
partner_url nvarchar(512) not null,
local_url nvarchar(512) not null,
public_url nvarchar(512) not null,
uniquehash AS HashBytes('SHA1',partner_url+local_url+public_url) PERSISTED,
primary key(id)
);
CREATE UNIQUE INDEX uniques ON url_tracker (install_date,uniquehash);
Thoughts?
I would make a computed column with the hash of the URLs, then make a unique index/constraint on that. Consider making the hash a persisted computed column. It shouldn't have to be recalculated after insertion.
Following the ideas from the conversation in the comments. Assuming that you can change the datatype of the URL to be VARCHAR(900) (or NVARCHAR(450) if you really think you need Unicode URLs) and be happy with the limitation on the length of the URL, this solution could work. This also assumes SQL Server 2008 or better. Please, always specify what version you're working with; sql-server is not specific enough, since solutions can vary greatly depending on the version.
Setup:
USE tempdb;
GO
CREATE TABLE dbo.urls
(
id INT IDENTITY(1,1) PRIMARY KEY,
url VARCHAR(900) NOT NULL UNIQUE
);
CREATE TABLE dbo.url_tracker
(
id INT IDENTITY(1,1) PRIMARY KEY,
active BIT NOT NULL DEFAULT 1,
install_date DATE NOT NULL DEFAULT CURRENT_TIMESTAMP,
partner_url_id INT NOT NULL REFERENCES dbo.urls(id),
local_url_id INT NOT NULL REFERENCES dbo.urls(id),
public_url_id INT NOT NULL REFERENCES dbo.urls(id),
CONSTRAINT unique_urls UNIQUE
(
install_date,partner_url_id, local_url_id, public_url_id
)
);
Insert some URLs:
INSERT dbo.urls(url) VALUES
('http://msn.com/'),
('http://aol.com/'),
('http://yahoo.com/'),
('http://google.com/'),
('http://gmail.com/'),
('http://stackoverflow.com/');
Now let's insert some data:
-- succeeds:
INSERT dbo.url_tracker(partner_url_id, local_url_id, public_url_id)
VALUES (1,2,3), (2,3,4), (3,4,5), (4,5,6);
-- fails:
INSERT dbo.url_tracker(partner_url_id, local_url_id, public_url_id)
VALUES(1,2,3);
GO
/*
Msg 2627, Level 14, State 1, Line 3
Violation of UNIQUE KEY constraint 'unique_urls'. Cannot insert duplicate key
in object 'dbo.url_tracker'. The duplicate key value is (2011-09-15, 1, 2, 3).
The statement has been terminated.
*/
-- succeeds, since it's for a different day:
INSERT dbo.url_tracker(install_date, partner_url_id, local_url_id, public_url_id)
VALUES('2011-09-01',1,2,3);
Cleanup:
DROP TABLE dbo.url_tracker, dbo.urls;
Now, if 900 bytes is not enough, you could change the URL table slightly:
CREATE TABLE dbo.urls
(
id INT IDENTITY(1,1) PRIMARY KEY,
url VARCHAR(2048) NOT NULL,
url_hash AS CONVERT(VARBINARY(32), HASHBYTES('SHA1', url)) PERSISTED,
CONSTRAINT unique_url UNIQUE(url_hash)
);
The rest doesn't have to change. And if you try to insert the same URL twice, you get a similar violation, e.g.
INSERT dbo.urls(url) SELECT 'http://www.google.com/';
GO
INSERT dbo.urls(url) SELECT 'http://www.google.com/';
GO
/*
Msg 2627, Level 14, State 1, Line 1
Violation of UNIQUE KEY constraint 'unique_url'. Cannot insert duplicate key
in object 'dbo.urls'. The duplicate key value is
(0xd111175e022c19f447895ad6b72ff259552d1b38).
The statement has been terminated.
*/
Using mySQLAdmin tool, I try to create a table. The tool generates the SQL statement, and then replorts a "Can't create table" with no other clue on what error it is!
Here it is :
CREATE TABLE `C121535_vubridge`.`Products` (
`pr_ID` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,
`pr_Name` VARCHAR(45) NOT NULL,
`pr_Type` VARCHAR(2) NOT NULL COMMENT 'H=Hand Series V=VuBridge software E=Event Subs S=Sponsoring',
`pr_AuthorID` INTEGER UNSIGNED COMMENT '= m_ID (for Bridge Hand Series',
`pr_SponsorID` INTEGER UNSIGNED NOT NULL,
`pr_DateCreation` DATETIME NOT NULL,
`pr_Price` FLOAT NOT NULL,
`pr_DescriptionText` TEXT,
`pr_Description` VARCHAR(245),
PRIMARY KEY (`pr_ID`),
CONSTRAINT `FK_prAuthor` FOREIGN KEY `FK_prAuthor` (`pr_AuthorID`)
REFERENCES `Members` (`m_ID`)
ON DELETE SET NULL
ON UPDATE NO ACTION,
CONSTRAINT `FK_Sponsor` FOREIGN KEY `FK_Sponsor` (`pr_SponsorID`)
REFERENCES `Members` (`m_ID`)
ON DELETE SET NULL
ON UPDATE NO ACTION
) ENGINE = InnoDB;
Can someone help?
The CREATE TABLE works for me if I omit the foreign key references:
CREATE TABLE `Products` (
`pr_ID` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,
`pr_Name` VARCHAR(45) NOT NULL,
`pr_Type` VARCHAR(2) NOT NULL COMMENT 'H=Hand Series V=VuBridge software E=Event Subs S=Sponsoring',
`pr_AuthorID` INTEGER UNSIGNED COMMENT '= m_ID (for Bridge Hand Series',
`pr_SponsorID` INTEGER UNSIGNED NOT NULL,
`pr_DateCreation` DATETIME NOT NULL,
`pr_Price` FLOAT NOT NULL,
`pr_DescriptionText` TEXT,
`pr_Description` VARCHAR(245),
PRIMARY KEY (`pr_ID`)
)
...so I'm inclined to believe that C121535_vubridge.MEMBERS does not already exist. C121535_vubridge.MEMBERS needs to be created before the CREATE TABLE statement for the PRODUCTS table is run.
Just split up the create table and try one part at the time. This way you should be able to identify a single line that it fails on.
I do note in the reference manual that if a symbol subclause is given for the CONSTRAINT clause (in your case, the back-quoted strings before FOREIGN KEY in each clause, FK_prAuthor and FK_Sponsor) have to be unique over the database. Are they? If not, that symbol can be omitted and InnoDB will assign then automatically.
Similarly, the tables your FKs refer to may not have the structure that this create statement expects.