system.hypothetical_projections

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Columns

• database (String) — Database name
• table (String) — Table name
• name (String) — Projection name
• type (Enum8(‘Normal’ = 0, ‘Aggregate’ = 1)) — Projection type
• sorting_key (Array(String)) — Projection sorting key
• query (String) — Projection SELECT query, empty for the INDEX … TYPE … form
• definition (String) — Full projection declaration as written
• settings (Map(String, String)) — Projection settings from WITH SETTINGS

CREATE HYPOTHETICAL PROJECTION p_by_b ON t (SELECT a, b ORDER BY b);
SELECT name, type, sorting_key FROM system.hypothetical_projections;

┌─name───┬─type───┬─sorting_key─┐
│ p_by_b │ Normal │ ['b']       │
└────────┴────────┴─────────────┘

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See also

• CREATE HYPOTHETICAL PROJECTION
• EXPLAIN WHATIF