CAP Troubleshooter

Diagnostic guide for common SAP Cloud Application Programming Model errors and issues.

Syntax Errors

Cause: Missing semicolon in CDS definition

Solution:

// ✓ CORRECT
entity Books {
  title : String(100);
  price : Decimal(10,2);
}

Cause: Referenced entity doesn't exist or isn't imported

Solution:

using { Authors } from './schema';
entity Books {
  author : Association to Authors;
}

Diagnostic Steps:

Solution:

# Validate MTA descriptor
mbt validate mta.yaml

# Clean build
rm -rf mta_archives/ .mta.* gen/
mbt build

Cause: Database not deployed

Solution:

# Deploy database schema
cds deploy --to sqlite:db/data.db

# For HANA
cds deploy --to hana

Cause: Missing or invalid JWT token

Solution:

// package.json - Enable authentication
{
  "cds": {
    "requires": {
      "auth": { "kind": "xsuaa" }
    }
  }
}

Solution:

// ✓ FAST: Single query with expand
const books = await SELECT.from(Books).columns(b => {
  b.*, b.author(a => a.*)
});