LazyFrame class final
- Available extensions
Properties
- hashCode → int
-
The hash code for this object.
no setterinherited
- isClosed → bool
-
no setter
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
batchStream(
{int batchRows = 65536, int capacity = 2, ExecutionEngine engine = ExecutionEngine.auto}) → Future< BatchStream> - Asynchronous transport variant of batchStreamSync.
-
batchStreamSync(
{int batchRows = 65536, int capacity = 2, ExecutionEngine engine = ExecutionEngine.auto}) → BatchStream - Starts bounded pull-based batch production on a native worker.
-
close(
) → void -
collect(
{ExecutionOptions options = const ExecutionOptions()}) → Future< DataFrame> -
collectSync(
{ExecutionOptions options = const ExecutionOptions()}) → DataFrame -
distinct(
{Iterable< String> ? subset, String keep = 'first', bool maintainOrder = false}) → LazyFrame -
drop(
Iterable< String> columns, {bool strict = true}) → LazyFrame -
dropNulls(
{Iterable< String> ? subset}) → LazyFrame -
explain(
{bool optimized = true, ExplainFormat format = ExplainFormat.plain}) → Future< String> -
explainSync(
{bool optimized = true, ExplainFormat format = ExplainFormat.plain}) → String -
explode(
Iterable< String> columns) → LazyFrame -
filter(
Expr predicate) → LazyFrame -
groupBy(
Iterable< Expr> keys, {bool maintainOrder = false}) → LazyGroupBy -
groupByDynamic(
Expr indexColumn, {Iterable< Expr> groupBy = const [], required DynamicGroupByOptions options}) → LazyDynamicGroupBy -
groupByRolling(
Expr indexColumn, {Iterable< Expr> groupBy = const [], required RollingGroupByOptions options}) → LazyRollingGroupBy -
head(
[int length = 5]) → LazyFrame -
join(
LazyFrame other, {required Iterable< Expr> leftOn, required Iterable<Expr> rightOn, String how = 'inner', String suffix = '_right', bool coalesce = false}) → LazyFrame -
joinAsOf(
LazyFrame other, {required Expr leftOn, required Expr rightOn, AsOfJoinOptions options = const AsOfJoinOptions()}) → LazyFrame -
joinWhere(
LazyFrame other, Iterable< Expr> predicates, {JoinWhereOptions options = const JoinWhereOptions()}) → LazyFrame -
joinWithOptions(
LazyFrame other, {required Iterable< Expr> leftOn, required Iterable<Expr> rightOn, JoinOptions options = const JoinOptions()}) → LazyFrame - Typed counterpart to join. The legacy string-based API remains intact.
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
profileSync(
{OptimizerOptions optimizer = const OptimizerOptions()}) → ProfileResult - Runs Polars' in-memory profiler and returns both frames as one result.
-
rename(
Map< String, String> mapping, {bool strict = true}) → LazyFrame -
schema(
) → Future< List< Field> > -
schemaSync(
) → List< Field> -
select(
Iterable< Expr> expressions) → LazyFrame -
selectInputs(
Iterable< Object> expressions) → LazyFrame - Projection accepting both Expr and Selector inputs.
-
selectSelectors(
Iterable< Selector> selectors) → LazyFrame -
sinkCsv(
String path, {bool? includeHeader, String? separator, CsvWriteOptions csv = const CsvWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
-
sinkCsvSync(
String path, {bool? includeHeader, String? separator, CsvWriteOptions csv = const CsvWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
Executes a native streaming CSV sink synchronously on the calling isolate. -
sinkFeatherSync(
String path, {IpcWriteOptions ipc = const IpcWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
-
sinkIpc(
String path, {IpcWriteOptions ipc = const IpcWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
-
sinkIpcSync(
String path, {IpcWriteOptions ipc = const IpcWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
Executes a native streaming IPC/Feather file sink synchronously. -
sinkNdjson(
String path, {LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
-
sinkNdjsonSync(
String path, {LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
Executes a native streaming newline-delimited JSON sink synchronously. -
sinkParquet(
String path, {String? compression, ParquetWriteOptions parquet = const ParquetWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
-
sinkParquetSync(
String path, {String? compression, ParquetWriteOptions parquet = const ParquetWriteOptions(), LazySinkOptions options = const LazySinkOptions()}) → void -
Available on LazyFrame, provided by the LocalIoLazyFrame extension
Executes a native streaming Parquet sink synchronously. -
slice(
int offset, int length) → LazyFrame -
sort(
Iterable< Expr> by, {Object descending = false, Object nullsLast = false, bool maintainOrder = false}) → LazyFrame -
submit(
{ExecutionOptions options = const ExecutionOptions()}) → Future< CancellableQuery> -
tail(
[int length = 5]) → LazyFrame -
toString(
) → String -
A string representation of this object.
inherited
-
unnest(
Iterable< String> columns) → LazyFrame -
unpivot(
{Iterable< String> ? on, Iterable<String> index = const [], String? variableName, String? valueName}) → LazyFrame -
withColumns(
Iterable< Expr> expressions) → LazyFrame -
withColumnSelectors(
Iterable< Selector> selectors) → LazyFrame -
withColumnsInputs(
Iterable< Object> expressions) → LazyFrame -
withColumnscounterpart accepting both Expr and Selector inputs. -
writeCsv(
String path, {bool? includeHeader, String? separator, CsvWriteOptions options = const CsvWriteOptions()}) → Future< void> - Compatibility Future wrapper around the native lazy sink. Depending on the transport, native execution may still occur on the calling isolate.
-
writeCsvSync(
String path, {bool? includeHeader, String? separator, CsvWriteOptions options = const CsvWriteOptions()}) → void -
writeParquet(
String path, {String? compression, ParquetWriteOptions options = const ParquetWriteOptions()}) → Future< void> - Compatibility Future wrapper around the native lazy sink. Depending on the transport, native execution may still occur on the calling isolate.
-
writeParquetSync(
String path, {String? compression, ParquetWriteOptions options = const ParquetWriteOptions()}) → void
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited