Can't create tables in Mysql

Question

I have these tables but only managed to create

1. Insurance_Policy_Type
2. Historical_Era
3. Region
4. Reference
5. Organisation
6. Geographic_Area

The rest of them are giving me errors such as,

"Cant create table" on Loan_Item,
"Reference_Id dont exist" on Historical_Era_Reference
"error 1064 (4200)" on Loan

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CREATE TABLE Insurance_Policy_Type (
Insurance_Policy_Type_Id INT (4),
Insurance_Policy_Type_Name VARCHAR (30),
PRIMARY KEY (Insurance_Policy_Type_Id));


CREATE TABLE Historical_Era (
Historical_Era_Id INT (4),
Historical_Era_Name VARCHAR (30),
PRIMARY KEY (Historical_Era_Id));


CREATE TABLE Reference (
Reference_Id INT (4),
Reference_Name VARCHAR (30),
Author VARCHAR (30),
PRIMARY KEY (Reference_Id));


CREATE TABLE Region (
Region_Id INT (4),
Region_Name VARCHAR (30),
PRIMARY KEY (Region_Id));

CREATE TABLE Organisation (
Organisation_Id INT (4),
Organisation_Name VARCHAR (30),
PRIMARY KEY (Organisation_Id));

CREATE TABLE Items (
Item_Id INT (4),
Item_Name VARCHAR (30),
Description VARCHAR (30),
Insurance_Policy_Type_Id INT (4),
Geo_Area_Id INT (4)
PRIMARY KEY (Item_Id),
FOREIGN KEY (Insurance_Policy_Type_Id) REFERENCES Insurance_Policy_Type(Insurance_Policy_Type_Id),
FOREIGN KEY (Geo_Area_Id) REFERENCES Geographic_Area(Geo_Area_Id));

CREATE TABLE GeoArea_HistEra (
Geo_Area_Id INT (4),
Historical_Era_Id INT (4),
FOREIGN KEY (Geo_Area_Id) REFERENCES Geographical_Area(Geo_Area_Id)),
FOREIGN KEY (Historical_Era_Id) REFERENCES Historical_Era(Historical_Era_Id));

CREATE TABLE Historical_Era_Reference (
References_Id INT (4),
Historical_Era_Id INT (4),
FOREIGN KEY (Reference_Id) REFERENCES Reference (Reference_Id),
FOREIGN KEY (Historical_Era_Id) REFERENCES Historical_Era (Historical_Era_Id));


CREATE TABLE Loan_Item (
Item_Id INT (4),
Loan_Id INT (4),
FOREIGN KEY (Item_Id) REFERENCES Items(Item_Id),
FOREIGN KEY (Loan_Id) REFERENCES Loan(Loan_Id));

CREATE TABLE Geographic_Area (
Geo_Area_Id INT (4),
Geo_Area_Name VARCHAR (30),
Region_Id INT (4),
PRIMARY KEY (Geo_Area_Id),
FOREIGN KEY (Region_Id) REFERENCES Region (Region_Id));

CREATE TABLE Loan (
Loan_Id INT (4),
Item_Id INT (4)
Organisation_Id INT(4)
Loan_Start DAY,
Loan_End DAY
FOREIGN KEY (Organisation_Id) REFERENCES Organisation (Organisation_Id),
FOREIGN KEY (Item_Id) REFERENCES Items (Item_Id));

Answer 1

There are plenty of issues with the query above.

1. You are making a reference to a table which doesn't exist yet: "FOREIGN KEY (Geo_Area_Id) REFERENCES Geographic_Area(Geo_Area_Id));" First create the table and then update the foreign keys.

2. There are plenty of syntax errors - missing commas and double brackets. Instead of pointing them one by one, I'd suggest learning how to spot them, for example I suggest using an IDE. I personally test statements in MySQL Workbench.

3. The query will likely produce an error 150, for a number of reasons. Please see a very good summary on typical errors with primary keys as FK in the first answer here.

Answer 2

Try to create the tables first and add the Foreign Keys later.