CREATE TABLE medico
(num_cedula serial NOT NULL UNIQUE,
nome varchar(20) NOT NULL,
especialidade varchar(20) NOT NULL,
PRIMARY KEY(num_cedula));
CREATE TABLE consulta
(num_cedula serial NOT NULL,
num_doente serial NOT NULL,
data_consulta date NOT NULL,
nome varchar(20) NOT NULL,
CHECK(EXTRACT(DOW FROM data_consulta) NOT IN (6,0)),
UNIQUE(num_doente,data_consulta,nome),
FOREIGN KEY(nome) REFERENCES instituicao(nome) ON UPDATE CASCADE,
FOREIGN KEY(num_cedula) REFERENCES medico(num_cedula) ON UPDATE CASCADE,
PRIMARY KEY(num_cedula,num_doente,data_consulta));
CREATE TABLE analise
(num_analise serial NOT NULL UNIQUE,
especialidade varchar(20) NOT NULL,
num_cedula serial ,
num_doente serial ,
data_analise date ,
data_registo date NOT NULL,
nome varchar(20) NOT NULL,
quant integer NOT NULL,
inst varchar(20) NOT NULL,
CONSTRAINT fk_analise FOREIGN KEY(num_cedula,num_doente,data_analise) REFERENCES consulta(num_cedula,num_doente,data_consulta) ON UPDATE CASCADE,
FOREIGN KEY(inst) REFERENCES instituicao(nome) ON UPDATE CASCADE,
PRIMARY KEY(num_analise));
This is my code but when I try to insert another "analise" with num_cedula,num_doente,data_analise as NULL it gives me this error ("ERROR: null value in column "num_cedula" violates not-null constraint
DETAIL: Failing row contains (32, Ortopedia, null, null, null, 2019-12-02, glicemia, 176, Instituicao1).
SQL state: 23502") and I don't really know why.
Also, this is the insert code I used:
INSERT INTO analise VALUES(32,'Ortopedia',NULL,NULL,NULL,'2019-12-02','glicemia',176,'Instituicao1');
The serial datatype just does not allow null values. The documentation explains what happens under the hood when declaring a serial (emphasis is mine):
Thus, we have created an integer column and arranged for its default values to be assigned from a sequence generator. A NOT NULL constraint is applied to ensure that a null value cannot be inserted.
I don't think that you really want serial here. The use case for that datatype is to create an auto-incremented column. You could probably use int instead, that would avoid the problem you are getting here.
Related
I have 2 tables and I want to create a foreign key constraint in the second table. This is what I tried:
Table 1:
CREATE TABLE REMINDER_RULE_M
(
REMINDER_RULE_M_D int IDENTITY(1,1) NOT NULL,
COMMUNICATION_MODE nvarchar(255) NOT NULL,
REMINDER_TO nvarchar(255) NOT NULL,
REMINDER_VALUE varchar(255) NOT NULL,
REMINDER_CONDITION varchar(255) NOT NULL,
REMINDER_TO_CUSTOM varchar(255)
)
Table 2:
CREATE TABLE REMINDER_AUDIT
(
REMINDER_AUDIT_D int IDENTITY(1,1) NOT NULL,
ACTION varchar(255) NOT NULL,
CONSTRAINT FK_b892318b20e5bbe162722ea5946
FOREIGN KEY (REMINDER_RULE_M_D)
REFERENCES REMINDER_RULE_M(REMINDER_RULE_M_D),
OLD_VALUE nvarchar(1024) NOT NULL,
NEW_VALUE nvarchar(1024) NOT NULL,
)
I get an error running the second SQL query:
Reason:
SQL Error [1769] [S0001]: Foreign key 'FK_b892318b20e5bbe162722ea5946' references invalid column 'REMINDER_RULE_M_D' in referencing table 'REMINDER_AUDIT'.
As the error clearly tells you - you don't have a column in your second table.
You must have a column in order to create a FK constraint - the FK constraint does NOT create a column in your table - it just establishes a constraint between existing tables and columns.
So try this for your second table:
CREATE TABLE REMINDER_AUDIT
(
REMINDER_AUDIT_D int IDENTITY(1,1) NOT NULL,
ACTION varchar(255) NOT NULL,
-- define the column!
REMINDER_RULE_M_D int NOT NULL,
-- I'd strongly recommend trying to come up with a more
-- intuitive and useful naming convention for your FK constraints!
CONSTRAINT FK_b892318b20e5bbe162722ea5946
FOREIGN KEY (REMINDER_RULE_M_D)
REFERENCES REMINDER_RULE_M(REMINDER_RULE_M_D),
OLD_VALUE nvarchar(1024) NOT NULL,
NEW_VALUE nvarchar(1024) NOT NULL,
)
I just guessed that REMINDER_RULE_M_D is NOT NULL - you might need to adapt this (if it's an optional key).
You do not need to write Foreign Key
CREATE TABLE REMINDER_AUDIT (
REMINDER_AUDIT_D int IDENTITY(1,1) NOT NULL,
ACTION varchar(255) NOT NULL,
CONSTRAINT FK_b892318b20e5bbe162722ea5946 REFERENCES REMINDER_RULE_M(REMINDER_RULE_M_D),
OLD_VALUE nvarchar(1024) NOT NULL,
NEW_VALUE nvarchar(1024) NOT NULL,
)
CREATE table Book
(
book_title varchar (100) not null ,
book_genre char(60) not null,
Date_of_publish date not null,
user_code char(7) not null ,
book_id char (7) primary key not null ,
constraint writer__id_fk foreign key (writer_id),
constraint publisher__id_fk foreign key (publisher_id)
);
I'm getting
[ORA-00905: missing keyword]
in publisher table
CREATE table publisher
(
publisher_id char (7) primary key not null,
publisher_name char(20) not null,
publisher_number char(10) not null,
publisher_email varchar2(60) not null,
publisher_address varchar2(60) not null,
);
I'm getting
[ORA-00904: : invalid identifier]
The following SQL creates a FOREIGN KEY on the "PersonID" column when the "Orders" table is created:
CREATE TABLE Orders (
OrderID int NOT NULL,
OrderNumber int NOT NULL,
PersonID int,
PRIMARY KEY (OrderID),
FOREIGN KEY (PersonID) REFERENCES Persons(PersonID)
);
Refer this link for more details
https://www.w3schools.com/sql/sql_foreignkey.asp
Hope this helps.
Welcome to the wonderful world of SQL! :-)
General remark:
Please tell us what kind of DBMS you're using. MySQL? SQL Server? Oracle? SQlite? Different systems use different kinds of syntaxes.
First statement:
The problem seems to be in the FOREIGN KEY-portion.
Usually, you'll state something like:
CONSTRAINT [constraint_name] FOREIGN KEY([column_in_this_table]) REFERENCES OTHER_TABLE([column_in_other_table])
edit (added):
The [column_in_this_table] has to exist in your DDL (CREATE TABLE-statement), like so:
CREATE TABLE Book ( book_title ... etc., publisher_id INT, CONSTRAINT FK_publ_id FOREIGN KEY(publisher_id) REFERENCES publisher(publisher_id));
Here, you'll have a 'original' column called 'publisher_id', in the 'publisher'-table. You refer to it from within the 'Book'-table, by first having a 'publisher_id' column in the 'Book'-table (which should have the same DDL as the original column by the way). Next, you'll add a FOREIGN KEY to the 'Book'-table, that is imposed on the Book(publisher_id) column. Note, that you could also name the column in your 'Book'-table differently -- like, say, 'Spongebob' or 'Patrick'. But for future use, you'd like naming conventions that tell what you might expect to find in a column. So you'd name columns for what they contain.
Second statement:
The problem is with the last portion of your statement, where there's a comma after the NOT NULL portion for column publisher_address.
(Part of) your statement:
publisher_address varchar2(60) not null, );
Try replacing that with:
publisher_address VARCHAR2(60) NOT NULL);
edit (note to self):
VARCHAR2 turns out to be a valid datatype in Oracle databases (see:
Oracle documentation)
For your first table, the Foreign Keys do not reference any table. For your second table, I would imagine that comma after your last column isn't helping anything.
So this is the answer.
CREATE table Book
(
book_title varchar (100) not null ,
book_genre char(60) not null,
Date_of_publish date not null,
user_code char(7) not null ,
publisher_id char (7) not null,
writer_id char(7) not null,
book_id char (7) primary key not null ,
CONSTRAINT book_writer_id_fk FOREIGN KEY(writer_id) REFERENCES writer(writer_id),
CONSTRAINT book_publisher_id_fk FOREIGN KEY(publisher_id) REFERENCES publisher(publisher_id)
);
CREATE table publisher
(
publisher_id char (7) primary key not null,
publisher_name char(20) not null,
publisher_number char(10) not null,
publisher_email varchar2(60) not null,
publisher_address varchar2(60) not null
);
I have 2 SQL statement as follows:
CREATE TABLE IF NOT EXISTS countries
(
country_id INT PRIMARY KEY NOT NULL AUTO_INCREMENT,
country varchar(45) NOT NULL
);
CREATE TABLE IF NOT EXISTS patients
(
p_id INT PRIMARY KEY NOT NULL AUTO_INCREMENT,
p_fname varchar(50) NOT NULL,
p_mname varchar(10) NULL,
p_lname varchar(50) NOT NULL,
age INT NOT NULL,
sex SET ('Male','Female'),
phone_num_mobile varchar(10) NULL,
phone_num_res varchar(7) NULL,
phone_num_office varchar(7) NULL,
email varchar(75) NULL,
addr_house varchar(10) NULL,
addr_street1 varchar(45) NOT NULL,
addr_street2 varchar(45) NULL,
addr_street3 varchar(45) NULL,
addr_city varchar(20) NOT NULL,
addr_country varchar(45) NOT NULL,
occupation varchar(20) NOT NULL,
married BOOLEAN NOT NULL,
FOREIGN KEY(addr_country) REFERENCES countries(country)
);
The first one executes successfully and the second one, which assigns a foreign key to the previous table, fails to execute with the message 'Foreign key constraint incorrectly formed'. I have also tried altering the second query's foreign key field(addr_country) to have the same name as that of the 'countries' table(country) but it were top no avail.
Can anyone please explain me what's going on and suggest me with a solution to this problem?
Thanks in advance.
A foreign key in MariaDB can only reference either a primary key in another table or a unique key. In this case, the countries table already has a primary key, so you can create a unique key on the country column.
Try putting a unique constraint on the country column in the countries table:
CREATE TABLE IF NOT EXISTS countries
(
country_id INT PRIMARY KEY NOT NULL AUTO_INCREMENT,
country varchar(45) NOT NULL
UNIQUE KEY(country)
);
Late edit: As the commentors mentioned, you might want to just reference the country_id primary key instead of the country name. Since no two countries in the world have the same name, either might work in practice.
I am trying to create a table in oracle but I am getting this error: unknown command ")" - rest of line ignored. I can't figure out what is causing this error. Below is my SQL for the table:
CREATE TABLE PAYMENT
(PayNum INT NOT NULL PRIMARY KEY,
CType VARCHAR(1) NOT NULL,
CCNum VARCHAR(16) NOT NULL,
BankName VARCHAR(75) NOT NULL,
AccNum INT NOT NULL,
PDate DATE NOT NULL,
Amt DECIMAL(11,2) NOT NULL,
CONSTRAINT fk_BANKACC_PAYMENT FOREIGN KEY (BankName, AccNum)
REFERENCES BANKACC(BankName, AccNum),
CONSTRAINT fk_CRCARD_PAYMENT FOREIGN KEY (CType, CCNum)
REFERENCES CRCARD(CType, CCNum)
);
Your code is correct. Make sure you are referencing primary keys (all 4).
Check this: http://sqlfiddle.com/#!2/7be70/1/0
If you do not follow that, you may get this error: There are no primary or candidate keys in the referenced table 'BANKACC' that match the referencing column list in the foreign key 'fk_BANKACC_PAYMENT'.
Code in the fiddle above:
CREATE TABLE BANKACC
(BankName VARCHAR(75) NOT NULL,
AccNum INT NOT NULL,
PRIMARY KEY(BankName, AccNum));
CREATE TABLE CRCARD
(CType VARCHAR(1) NOT NULL,
CCNum VARCHAR(16) NOT NULL,
PRIMARY KEY(CType, CCNum));
CREATE TABLE PAYMENT
(PayNum INT NOT NULL PRIMARY KEY,
CType VARCHAR(1) NOT NULL,
CCNum VARCHAR(16) NOT NULL,
BankName VARCHAR(75) NOT NULL,
AccNum INT NOT NULL,
PDate DATE NOT NULL,
Amt DECIMAL(11,2) NOT NULL,
CONSTRAINT fk_BANKACC_PAYMENT FOREIGN KEY (BankName, AccNum)
REFERENCES BANKACC(BankName, AccNum),
CONSTRAINT fk_CRCARD_PAYMENT FOREIGN KEY (CType, CCNum)
REFERENCES CRCARD(CType, CCNum)
);
Also you should read this for better understanding on how to implement foreign key constraint: http://docs.oracle.com/cd/E17952_01/refman-5.5-en/create-table-foreign-keys.html
If you're running this in SQL*Plus, get rid of the blank line between REFERENCES and ):
REFERENCES CRCARD(CType, CCNum)
);
Or set sqlblanklines on to change the behaviour.
By default it interprets a blank line as the end of the statement, but doesn't run it. So your entire CREATE TABLE command is essentially ignored, and the ); is treated as a stanalone command. Hence the error message you get, since it doesn't mean anything on its own.
Please use NUMBER for numeric columns.
http://docs.oracle.com/cd/B28359_01/server.111/b28318/datatype.htm#CNCPT313
Also, in Oracle, use VARCHAR2 for strings.
but of it your syntax should be correct.
I am creating two tables. The first table creates with no errors, but when I try to create the SUBHEAD table, I get an error: Line 2, Missing right parenthesis. I am not sure what is wrong with this line. Below is my SQL statements:
CREATE TABLE HEAD
(Code NUMERIC(4,0) NOT NULL PRIMARY KEY,
HeadName VARCHAR(50) NOT NULL UNIQUE,
HType VARCHAR(1) NOT NULL,
HDate DATE NOT NULL,
OpBal DECIMAL(11,2) NOT NULL
);
CREATE TABLE SUBHEAD
(HCode NUMERIC(4,0) NOT NULL FOREIGN KEY REFERENCES HEAD(Code),
SubCode NUMERIC(4,0) NOT NULL,
SubName VARCHAR(50) NOT NULL,
SDate DATE NOT NULL,
OpBal DECIMAL (11,2) NOT NULL,
CONSTRAINT pk_subheadID PRIMARY KEY (HCode, SubCode)
);
syntax: http://docs.oracle.com/cd/B28359_01/server.111/b28286/clauses002.htm#SQLRF52167
note that "in-line" constraint syntax is : "col col_type REFERENCES TAB(COL)" and not "FOREIGN KEY"
The data type for number is NUMBER not NUMERIC
So my memory did not fool me - you can have multiple in-line constraints (although the syntax graph doesn't show it):
SQL> create table tt1(a number primary key);
Table created.
SQL> create table tt2(a number references tt1(a) not null);
Table created.
CREATE TABLE SUBHEAD
(HCode NUMERIC(4,0) NOT NULL, FOREIGN KEY (Hcode) REFERENCES HEAD(Code),
SubCode NUMERIC(4,0) NOT NULL,
SubName VARCHAR(50) NOT NULL,
SDate DATE NOT NULL,
OpBal DECIMAL (11,2) NOT NULL,
CONSTRAINT pk_subheadID PRIMARY KEY (HCode, SubCode)
);
(note comma, and reference to the new table column)