Migrating to Polars py-1.33.0
Version py-1.33.0 introduces 1 breaking change. This guide details how to update your code.
Released: 9/1/2025
1
Breaking Changes
0
Migration Steps
39
Affected Symbols
⚠️ Check Your Code
If you use any of these symbols, you need to read this guide:
Exprint_rangearg_uniquearg_whereExpr.shiftgroupbypl.Series.shiftpl.Expr.logwrite_parquetdiff()Expr.diffpl.DataFrame.map_columnsdt.epochExpr.rechunkfrom_pandaspl.LazyFrame.pipe_with_schemacum_*peak\_{min,max}map_groupsLazyGroupBy.headLazyGroupBy.tailgatherto_arrowgroup_by_dynamicgroup_bypartition_byrolling_meanread_databasePyCategoriesto_mutable_slicetop_ksort_bymerge_sortedrow_encodefoldreduceExpr.meta.output_namepl.DatemeanBreaking Changes
●Issue #1
Removed, deprecated, or changed eager Exprs to be lazy compatible. Users relying on eager evaluation of expressions that are now lazy might see changes in execution behavior or errors if they expected immediate results.
Release Summary
This release focuses heavily on performance improvements by lowering many operations natively to the streaming engine and optimizing the query planner. A significant breaking change involves making previously eager Exprs lazy compatible.
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View the full release notes and all changes for Polars py-1.33.0.
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