Module schema 

Runtime schema assertion for derived entities.

Generated repositories build their SQL from entity metadata, so a drifted table (renamed column, missed migration, nullability change) surfaces as a runtime decode error instead of a compile error. This module restores an equivalent guarantee with one integration test: compare every entity’s declared columns against information_schema.columns and report all mismatches at once.

#[sqlx::test]
async fn schema_matches(pool: PgPool) {
    User::assert_schema(&pool).await.expect("users drifted");
    Parcel::assert_schema(&pool).await.expect("parcels drifted");
}

Type comparison

Declared SQL types are normalised before comparison (TEXT ↔ character varying ↔ character are one text family; parametrised types drop their arguments; arrays compare as arrays). Columns whose database type is USER-DEFINED (Postgres enums, domains) skip the type check — the macro cannot know the enum’s SQL name unless #[column(pg_enum = ...)] is used, and presence + nullability still guard those columns.

Structs

SchemaColumn

Declared shape of one entity column.

SchemaMismatch

All divergences found for one table.

TableSchema

Declared shape of an entity’s table.

Enums

SchemaCheckError

Errors from the assertion itself (query failure vs. actual drift).

SchemaDrift

One detected divergence between the entity and the live table.

Functions

assert_table

Compare a declared table shape against the live database.