Impact and load order

Two panels that answer operational questions straight from the model.

Impact analysis#

Before you delete or change something, find out what depends on it. Open the target icon in the toolbar, then click a table, view, column, schema or catalog.

• Red: downstream. Everything that depends on the selection (foreign keys, views, dashed lineage lines) turns red. Unaffected objects fade.
• Blue: upstream. Everything the selection depends on.
• Amber: review first. Nothing depends on it, but it depends on something (a table with foreign keys, a view). The panel says Not safe to delete without a review.
• Green: safe. Nothing depends on it and it depends on nothing. A plain column no key or view uses is safe; a table almost never is.

Unused columns are listed too.

Impact analysis sees what is in the model. Applications outside the model that read your tables are still yours to check.

Load order#

Open the stacked-boxes icon. It shows which tables must load first, which can load at the same time, and what waits for what.

• Stages. Stage 1 needs nothing else (reference data). Stage 2 needs only stage 1, and so on. Tables in one stage can load in parallel. The summary shows the number of stages, the widest stage and the longest chain.
• Stages, Pipeline or Tree. Pipeline draws the stages as columns with arrows between tables (solid = foreign key, dashed = a view reads it). Also full screen.
• Click a table: what must load before it turns blue, what waits for it turns orange.
• Views are placed after the tables they read.
• Circular dependencies are flagged with a red cycle tag: load them together, then add the foreign keys. A self-reference is marked self-ref and does not change the order.

SLA: when is the data ready?#

Give tables a data availability SLA (realtime to yearly, a 24-hour time, or Out of SLA). The panel then shows each table's own SLA and its cumulative ready time: the later of its own SLA and the ready time of everything it needs. It also shows when the first data arrives, when the last data is ready, the duration between them, and the path of the last data to arrive. A yellow warning means a table promises data earlier than its inputs can deliver.

Export#

Export the sequence as JSON (<model>.load-order.json), or turn it into a starter pipeline: see Share and AI.

On the conceptual and logical levels, both panels work from the tables behind each concept or entity. Load order is not available on the Semantic level.