fix: add missing end_snapshot IS NULL filter in Postgres and MySQL providers#88
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zfarrell merged 1 commit intoMar 18, 2026
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…t_table_structure() The PostgreSQL and MySQL metadata providers were missing 'AND end_snapshot IS NULL' in get_table_structure(), causing all historical column rows to be returned instead of only current ones. When a column's properties change (e.g. nullability), DuckLake closes the old row (end_snapshot = N) and creates a new one (end_snapshot = NULL). Without the filter, both rows are returned, creating duplicate column names in the Arrow schema, which DataFusion rejects with: Schema error: Schema contains duplicate qualified field name The DuckDB provider already has this filter via the shared SQL_GET_TABLE_COLUMNS constant. The SQLite provider has it in its inline SQL. Only PostgreSQL and MySQL were missing it.
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Thanks @ChristianCasazza! |
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Fixes #87.
The Postgres and MySQL
get_table_structure()queries were missingAND end_snapshot IS NULL, returning expired column rows alongside current ones. This causes duplicate column names in the Arrow schema when a column's properties have changed over time.The DuckDB and SQLite providers already have this filter. Two lines changed, one in each file.