Description

In CDS 10, Decimal elements are mapped to the REAL affinity in SQLite instead of the previous NUMERIC affinity. SQLite's REAL affinity stores values as 8-byte IEEE 754 floating-point numbers, while NUMERIC affinity tried to store values as integers when possible. This change only affects local development and testing environments that use SQLite — production HANA deployments are not affected. Test assertions that relied on the precision or rounding behavior of NUMERIC affinity (e.g. exact decimal comparisons) may fail after the upgrade.

How to Check

• [ ] Check cds env output for cds.requires.db.decimal_affinity — if absent, the new REAL default applies for SQLite.
• [ ] Search CDL files for Decimal element definitions to identify the scope of affected data.
• [ ] Run the test suite against the upgraded environment and check for assertion failures on Decimal-typed fields.
• [ ] Review test assertions that compare Decimal values with exact equality (e.g. expect(result.price).toBe(9.99)) — floating-point representation differences may cause failures.

Migration Steps

1. If the new REAL affinity behavior is acceptable (most cases), no change is needed — the new default applies automatically. Verify by running the test suite.

2. Update test assertions that relied on NUMERIC affinity rounding behavior to be floating-point-tolerant:

   - expect(result.price).toBe(9.99);
   + expect(result.price).toBeCloseTo(9.99, 5);

3. If you need time to update tests, temporarily set the compat flag to restore the previous NUMERIC affinity:

   // package.json or .cdsrc.json
   {
     "cds": {
       "requires": {
         "db": {
   +       "decimal_affinity": "NUMERIC"
         }
       }
     }
   }

   Remove the flag once test assertions are updated to handle REAL affinity values.

Notes

The change only affects SQLite (local development and automated test runs). HANA Cloud stores Decimal with full precision regardless of this setting. Projects that run tests exclusively against HANA (e.g. in CI against a HANA service instance) are not affected by this change.