Hi All,
I'm having trouble creating my database (airport database).
After charing my database with this forum concerning another topic, I was advised to rething the structure of my tables.
I'm not 100% sure I comply with the 3 rules of normalizations. The reason I not 100% sure is because when I try to create my relationship it doesn't work.
I created 2 tables : tbl_Aiport_info, tbl_Runway
For example, in the table Airport_info I have the data concerning a unique airport. In the table Runway, the data is unique for a specfic runway but a unique Airport can have multiple runways.
So, in the table Airport_info, I created a primary key (ICAO) which identifies a unique airport. In the table Runway, I created a primary key (RunwayName) which is unique, and I added a field ICAO (to be able to link the table Airport_info with the table Runway).
In addition, the field ICAO in both tables have the same proprety and the same Data type.
When I try to create a relationship between my two tables with a "one-to-many" type. I tick "enforce referential integrity, cascade update related fields and cascade delete related records". However, the relation won't work because apparently (From Access) "the data in the table Runway violates referential rules".
I've done my researche on referenial integrity rules. 3 rules existe :
1- In the parenting table, the related field must be a primary key.
2- The related fields in both tables must be of compatible data type.
3- Both tables must belong to the same database
I have the impression I comply with all 3 rules of referential integrity. However, the "one-to-many" relation won't work.
I've attached my database so you can have a look.
Thank you for your help,
Mat
I'm having trouble creating my database (airport database).
After charing my database with this forum concerning another topic, I was advised to rething the structure of my tables.
I'm not 100% sure I comply with the 3 rules of normalizations. The reason I not 100% sure is because when I try to create my relationship it doesn't work.
I created 2 tables : tbl_Aiport_info, tbl_Runway
For example, in the table Airport_info I have the data concerning a unique airport. In the table Runway, the data is unique for a specfic runway but a unique Airport can have multiple runways.
So, in the table Airport_info, I created a primary key (ICAO) which identifies a unique airport. In the table Runway, I created a primary key (RunwayName) which is unique, and I added a field ICAO (to be able to link the table Airport_info with the table Runway).
In addition, the field ICAO in both tables have the same proprety and the same Data type.
When I try to create a relationship between my two tables with a "one-to-many" type. I tick "enforce referential integrity, cascade update related fields and cascade delete related records". However, the relation won't work because apparently (From Access) "the data in the table Runway violates referential rules".
I've done my researche on referenial integrity rules. 3 rules existe :
1- In the parenting table, the related field must be a primary key.
2- The related fields in both tables must be of compatible data type.
3- Both tables must belong to the same database
I have the impression I comply with all 3 rules of referential integrity. However, the "one-to-many" relation won't work.
I've attached my database so you can have a look.
Thank you for your help,
Mat