Class DatabaseDesignerPipelineExecutor

Create or modify multiple entities in a single pipeline batch — one CodeGen run covers all tables, which is the primary performance benefit over calling CreateEntity/ModifyEntity individually.

Execution sequence:

1. Sort tables by FK dependency so referenced tables are created first
2. For each table: normalise FKs + generate migration SQL (CREATE or ALTER)
3. Run RuntimeSchemaManager.RunPipelineBatch() — one lock, one CodeGen run
4. Refresh metadata once after all migrations complete
5. Save provenance (MJ:UDT:Owner, MJ:UDT:Source) for every successful table

Partial failure is supported: if 3 of 5 tables succeed and 2 fail, the successful tables are live in the DB, CodeGen runs on them, and the caller receives per-table Success flags to present to the user.

Create a new entity: generate migration SQL, execute the RSU pipeline, refresh metadata, and persist provenance settings.

Load the physical column information for an existing table from MJ's Entity Fields metadata. Returns null if the table is not known to MJ.

Shared by both the Schema Builder agent (alter path) and the Modify Entity action so there is a single, correct implementation — including Precision and Scale which are required for SchemaEvolution to correctly diff numeric column changes.

Modify an existing entity: diff desired vs existing schema, generate ALTER TABLE migration SQL, execute the RSU pipeline, and refresh metadata.

Sort table definitions so that tables referenced by FK from other tables in the batch appear BEFORE the tables that reference them.

Uses Kahn's topological sort algorithm — runs in O(V+E) time where V is the number of tables and E is the number of FK relationships within the batch. Tables with no intra-batch FK dependencies retain their original relative order (stable sort property of Kahn's algorithm with a queue).

If a circular FK dependency exists (which SchemaEngine would reject during DDL generation anyway), the cycle is detected and the remaining tables are appended in original order so the batch does not silently drop tables.