sap-cds-erd

= SAP CDS Entity Relationship Diagrams :hide-uri-scheme:

The small AWK script generate https://mermaid.js.org/[mermaid] Entity Relationship diagrams from SAP Cloud Application Programming Model files.

== How to run script

[source,shell]

gawk -f src/cds2erd.awk db/* > bookstore.mermaid

Alternatively, you can move the script to the bin directory and make it executable:

[source,shell]

chmod +x cds2erd.awk

In this case you can call the script without specifying an interpreter:

[source,shell]

cds2erd.awk schema.cds > schema.mermaid

== Sample generated ER diagram

Below is the database schema from the project https://github.com/SAP-samples/cloud-cap-samples/[SAP Cloud CAP Samples Bookstore]

[source,mermaid]

erDiagram Books { String title String descr Integer stock Decimal price Currency currency Decimal rating TechnicalBooleanFlag isReviewable }

Authors {
    String name 
    Date dateOfBirth 
    Date dateOfDeath 
    String placeOfBirth 
    String placeOfDeath 
}

Genres {
    String name 
    String descr 
    Integer ID PK
}

Notes {
    String note 
}

Orders {
    String OrderNo 
    User buyer 
    Decimal total 
    Currency currency 
}

OrderItems {
    Integer quantity 
    Decimal amount 
}

Reviews {
    Rating rating 
    String title 
    String text 
}

Orders |o--o{ OrderItems : ""
OrderItems |o--o| Books : ""
Genres }o--o| Genres : ""
Books |o--o{ Reviews : ""
Books |o--o| Genres : ""
Books }o--o| Authors : ""