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Partial, Expression, and Functional Indexes/MySQL generated column from JSON

Make a JSON path searchable with an index.

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Section: Pattern catalog

MySQL generated column from JSON

sql
sql
ALTER TABLE events
  ADD COLUMN event_type VARCHAR(64) GENERATED ALWAYS AS (JSON_UNQUOTE(JSON_EXTRACT(payload, '$.type'))) STORED,
  ADD INDEX idx_events_event_type (event_type);
Explanation

Generated columns are a common way to index computed values in MySQL.

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