CalciteBuilder¶

Public API¶

class modin.experimental.engines.omnisci_on_native.frame.calcite_builder.CalciteBuilder¶

Translator used to transform DFAlgNode tree into a calcite node sequence.

class CompoundAggregate(builder, arg)¶

A base class for a compound aggregate translation.

Translation is done in three steps. Step 1 is an additional values generation using a projection. Step 2 is a generation of aggregates that will be later used for a compound aggregate value computation. Step 3 is a final aggregate value generation using another projection.

Parameters

builder (CalciteBuilder) – A builder to use for translation.
arg (BaseExpr) – An aggregated value.

gen_agg_exprs()¶

Generate intermediate aggregates required for a compound aggregate computation.

Returns: New aggregate expressions mapped to their names.
Return type: dict

gen_proj_exprs()¶

Generate values required for intermediate aggregates computation.

Returns: New column expressions mapped to their names.
Return type: dict

gen_reduce_expr()¶

Generate an expression for a compound aggregate.

Returns: A final compound aggregate expression.
Return type: BaseExpr

class InputContext(input_frames, input_nodes)¶

A class to track current input frames and corresponding nodes.

Used to translate input column references to numeric indices.

Parameters

input_frames (list of DFAlgNode) – Input nodes of the currently translated node.
input_nodes (list of CalciteBaseNode) – Translated input nodes.

input_nodes¶

Input nodes of the currently translated node.

Type: list of CalciteBaseNode

frame_to_node¶

Maps input frames to corresponding calcite nodes.

Type: dict

input_offsets¶

Maps input frame to an input index used for its first column.

Type: dict

replacements¶

Maps input frame to a new list of columns to use. Used when a single DFAlgNode is lowered into multiple computation steps, e.g. for compound aggregates requiring additional projections.

Type: dict

input_ids()¶

Get ids of all input nodes.

Returns
Return type: list of int

ref(frame, col)¶

Translate input column into CalciteInputRefExpr.

Parameters

frame (DFAlgNode) – An input frame.
col (str) – An input column.

Returns

Return type

CalciteInputRefExpr

ref_idx(frame, col)¶

Translate input column into CalciteInputIdxExpr.

Parameters

frame (DFAlgNode) – An input frame.
col (str) – An input column.

Returns

Return type

CalciteInputIdxExpr

replace_input_node(frame, node, new_cols)¶

Use node as an input node for references to columns of frame.

Parameters

frame (DFAlgNode) – Replaced input frame.
node (CalciteBaseNode) – A new node to use.
new_cols (list of str) – A new columns list to use.

translate(expr)¶

Translate an expression.

Translation is done by replacing InputRefExpr with CalciteInputRefExpr and CalciteInputIdxExpr.

Parameters: expr (BaseExpr) – An expression to translate.
Returns: Translated expression.
Return type: BaseExpr

class InputContextMgr(builder, input_frames, input_nodes)¶

A helper class to manage an input context stack.

The class is designed to be used in a recursion with nested ‘with’ statements.

Parameters

builder (CalciteBuilder) – An outer builder.
input_frames (list of DFAlgNode) – Input nodes for the new context.
input_nodes (list of CalciteBaseNode) – Translated input nodes.

builder¶

An outer builder.

Type: CalciteBuilder

input_frames¶

Input nodes for the new context.

Type: list of DFAlgNode

input_nodes¶

Translated input nodes.

Type: list of CalciteBaseNode

class SkewAggregate(builder, arg)¶

An unbiased skew aggregate generator.

Parameters

builder (CalciteBuilder) – A builder to use for translation.
arg (BaseExpr) – An aggregated value.

gen_agg_exprs()¶

Generate intermediate aggregates required for a compound aggregate computation.

Returns: New aggregate expressions mapped to their names.
Return type: dict

gen_proj_exprs()¶

Generate values required for intermediate aggregates computation.

Returns: New column expressions mapped to their names.
Return type: dict

gen_reduce_expr()¶

Generate an expression for a compound aggregate.

Returns: A final compound aggregate expression.
Return type: BaseExpr

class StdAggregate(builder, arg)¶

A sample standard deviation aggregate generator.

Parameters

builder (CalciteBuilder) – A builder to use for translation.
arg (BaseExpr) – An aggregated value.

gen_agg_exprs()¶

Generate intermediate aggregates required for a compound aggregate computation.

Returns: New aggregate expressions mapped to their names.
Return type: dict

gen_proj_exprs()¶

Generate values required for intermediate aggregates computation.

Returns: New column expressions mapped to their names.
Return type: dict

gen_reduce_expr()¶

Generate an expression for a compound aggregate.

Returns: A final compound aggregate expression.
Return type: BaseExpr

build(op)¶

Translate a DFAlgNode tree into a calcite nodes sequence.

Parameters: op (DFAlgNode) – A tree to translate.
Returns: The resulting calcite nodes sequence.
Return type: list of CalciteBaseNode