# Architecture principles whose scope is schema

> 7 records

This index as JSON: https://banes-lab.com/json/api/facets/architecture/scope/schema

## Entries

- [Backward Compatibility](https://banes-lab.com/records/architecture/backward-compatibility.md): A rule or precondition that a new version keeps working for consumers written against an older one.
- [Forward Compatibility](https://banes-lab.com/records/architecture/forward-compatibility.md): A rule or precondition that an older reader accepts data from a newer writer by ignoring the fields it does not know rather than failing on them.
- [Versioning](https://banes-lab.com/records/architecture/versioning.md): A mechanism that labels each release of an interface or schema, so consumers can tell compatible changes from breaking ones.
- [Single Source of Truth](https://banes-lab.com/records/architecture/single-source-of-truth.md): A design rule that each fact, rule or configuration value has one owning definition, and every other value is derived from it.
- [Normalization](https://banes-lab.com/records/architecture/normalization.md): A technique for storing each fact once and referring to it by key wherever it is needed.
- [Database Normalization](https://banes-lab.com/records/architecture/database-normalization.md): A technique for decomposing tables by their functional dependencies into normal forms, so no column depends on anything but its key.
- [Joinable Mandated Field](https://banes-lab.com/records/architecture/joinable-mandated-field.md): A rule or precondition that a mandated field takes a value from a closed set or an identifier, or declares that it is written for readers, so a governed surface never looks measured on a property nothing can read.