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Legacy Parser Extension
DuckDB v2.0.0 replaced the PostgreSQL-derived parser with a new PEG-based parser.
The legacy_parser extension allows reverting to the old parser.
The PEG parser is designed to be compatible with the previous parser, so queries that parsed before should continue to parse. If a query that parsed on an earlier version fails on v2.0.0, please file an issue.
Installing and Loading
To install and load the legacy_parser extension, run:
INSTALL legacy_parser;
LOAD legacy_parser;
Usage
To activate the legacy parser, run:
SET enable_legacy_parser = true;
To switch back to the PEG parser, run:
SET enable_legacy_parser = false;
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