Macros

Altertable catalogs support scalar and table macros created with standard CREATE MACRO syntax. Macros are stored in catalog metadata and can be referenced from queries, view definitions, and sort-order expressions.

Macros participate in time travel — querying a catalog at an earlier snapshot reflects the macros that existed at that point.

Run the statements below through Altertable's SQL engine against an Altertable catalog you own.

Scalar macros

Scalar macros return a single value:

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CREATE MACRO margin_pct(price, cost) AS (price - cost) / price * 100;

SELECT margin_pct(49.99, 31.50);

Table macros

Table macros return a table:

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CREATE MACRO high_stock_skus(min_qty) AS TABLE
  SELECT sku, warehouse_id, on_hand
  FROM my_catalog.main.inventory_levels
  WHERE on_hand >= min_qty;

SELECT * FROM high_stock_skus(500);

Default parameters

Macros can define default values for parameters:

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CREATE MACRO apply_discount(price, pct := 10) AS price * (1 - pct / 100.0);

SELECT apply_discount(120.00);

Typed parameters

Macros can specify types for their parameters:

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CREATE MACRO pallet_count(units INTEGER, units_per_pallet INTEGER) AS ceil(units / units_per_pallet);

Drop macros

Drop scalar macros with DROP MACRO and table macros with DROP MACRO TABLE:

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DROP MACRO margin_pct;
DROP MACRO TABLE high_stock_skus;

When to use macros

Use macros to centralize repeated expressions — date bucketing, unit conversions, or shared filter logic — so queries stay readable and changes propagate from one definition.

For sort orders and views that depend on a macro, define the macro before referencing it in SET SORTED BY or CREATE VIEW.

Learn more

• Sorted Tables: Use macros in expression-based sort keys
• Views: Encapsulate queries behind stable names
• SQL Engine: DuckDB dialect and federated queries