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Posted to github@arrow.apache.org by GitBox <gi...@apache.org> on 2022/02/23 17:08:28 UTC
[GitHub] [arrow] jorisvandenbossche commented on a change in pull request #12452: ARROW-14292: [C++][Python] Join foundation for Tables
jorisvandenbossche commented on a change in pull request #12452:
URL: https://github.com/apache/arrow/pull/12452#discussion_r813057027
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
Review comment:
```suggestion
Internal Function to create an ExecPlan and run it.
```
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
+
+ Parameters
+ ----------
+ inputs : list of Table or Dataset
+ The sources from which the ExecPlan should fetch data.
+ In most cases this is only one, unless the first node of the
+ plan is able to get data from multiple different sources.
+ output_type : Table or Dataset
+ In which format the output should be provided.
+ plan : vector[CDeclaration]
+ The nodes of the plan that should be applied to the sources
+ to produce the output.
+ """
+ cdef:
+ CExecContext c_exec_context = CExecContext(c_default_memory_pool(),
+ GetCpuThreadPool())
Review comment:
Do we want an option to not use threads for executing this plan? (I don't know if that is possible right now with the interface)
In other places in pyarrow we use a `use_threads` keyword to toggle this
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
+
+ Parameters
+ ----------
+ inputs : list of Table or Dataset
Review comment:
At the moment it is only Table and not Dataset, right?
##########
File path: python/pyarrow/includes/libarrow.pxd
##########
@@ -1784,11 +1788,26 @@ cdef extern from "arrow/json/reader.h" namespace "arrow::json" nogil:
CResult[shared_ptr[CTable]] Read()
+cdef extern from "arrow/util/thread_pool.h" namespace "arrow::internal" nogil:
Review comment:
We already have the declaration for `GetCpuThreadPoolCapacity` from `thread_pool.h` somewhere in this file, maybe move them together?
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
+
+ Parameters
+ ----------
+ inputs : list of Table or Dataset
+ The sources from which the ExecPlan should fetch data.
+ In most cases this is only one, unless the first node of the
+ plan is able to get data from multiple different sources.
+ output_type : Table or Dataset
+ In which format the output should be provided.
+ plan : vector[CDeclaration]
+ The nodes of the plan that should be applied to the sources
+ to produce the output.
+ """
+ cdef:
+ CExecContext c_exec_context = CExecContext(c_default_memory_pool(),
+ GetCpuThreadPool())
+ shared_ptr[CExecPlan] c_exec_plan = GetResultValue(CExecPlan.Make(&c_exec_context))
+ vector[CDeclaration] c_decls
+ vector[CExecNode*] _empty
+ vector[CExecNode*] c_final_node_vec
+ CExecNode *c_node
+ CTable* c_table
+ shared_ptr[CTable] c_out_table
+ shared_ptr[CSourceNodeOptions] c_sourceopts
+ shared_ptr[CSinkNodeOptions] c_sinkopts
+ shared_ptr[CAsyncExecBatchGenerator] c_asyncexecbatchgen
+ shared_ptr[CRecordBatchReader] c_recordbatchreader
+ vector[CDeclaration].iterator plan_iter
+
+ plan_iter = plan.begin()
+
+ # Create source nodes for each input
+ for ipt in inputs:
+ if isinstance(ipt, Table):
+ c_in_table = pyarrow_unwrap_table(ipt).get()
+ c_sourceopts = GetResultValue(
+ CSourceNodeOptions.FromTable(deref(c_in_table), c_exec_context.executor()))
+ else:
+ raise TypeError("Unsupproted type")
+
+ if plan_iter != plan.end():
+ # Flag the source as the input of the first plan node.
+ deref(plan_iter).inputs.push_back(CDeclaration.Input(
+ CDeclaration(tobytes("source"), deref(c_sourceopts))
+ ))
+ else:
+ # Empty plan, make the source the first plan node.
+ c_decls.push_back(
+ CDeclaration(tobytes("source"), deref(c_sourceopts))
+ )
+
+ # Add Here additional nodes
+ while plan_iter != plan.end():
+ c_decls.push_back(deref(plan_iter))
+ inc(plan_iter)
+
+ # Add all CDeclarations to the plan
+ c_node = GetResultValue(
+ CDeclaration.Sequence(c_decls).AddToPlan(&deref(c_exec_plan))
+ )
+ c_final_node_vec.push_back(c_node)
+
+ # Create the output node
+ c_asyncexecbatchgen = make_shared[CAsyncExecBatchGenerator]()
+ c_sinkopts = make_shared[CSinkNodeOptions](c_asyncexecbatchgen.get())
+ GetResultValue(
+ MakeExecNode(tobytes("sink"), &deref(c_exec_plan),
+ c_final_node_vec, deref(c_sinkopts))
+ )
+
+ # Convert the asyncgenerator to a sync batch reader
+ c_recordbatchreader = MakeGeneratorReader(c_node.output_schema(),
+ deref(c_asyncexecbatchgen),
+ c_exec_context.memory_pool())
+
+ # Start execution of the ExecPlan
+ deref(c_exec_plan).Validate()
+ deref(c_exec_plan).StartProducing()
+
+ # Convert output to the expected one.
+ if output_type == Table:
+ c_out_table = GetResultValue(
+ CTable.FromRecordBatchReader(c_recordbatchreader.get()))
+ output = pyarrow_wrap_table(c_out_table)
+ else:
+ raise TypeError("Unsupported output type")
+
+ deref(c_exec_plan).StopProducing()
+
+ return output
+
+
+def tables_join(join_type, left_table, left_keys, right_table, right_keys):
Review comment:
`join_tables` sounds/reads more natural than `tables_join` IMO (subjective of course)
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
+
+ Parameters
+ ----------
+ inputs : list of Table or Dataset
+ The sources from which the ExecPlan should fetch data.
Review comment:
small nit, but indentation is a bit off here
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
+
+ Parameters
+ ----------
+ inputs : list of Table or Dataset
+ The sources from which the ExecPlan should fetch data.
+ In most cases this is only one, unless the first node of the
+ plan is able to get data from multiple different sources.
+ output_type : Table or Dataset
+ In which format the output should be provided.
+ plan : vector[CDeclaration]
+ The nodes of the plan that should be applied to the sources
+ to produce the output.
+ """
+ cdef:
+ CExecContext c_exec_context = CExecContext(c_default_memory_pool(),
+ GetCpuThreadPool())
+ shared_ptr[CExecPlan] c_exec_plan = GetResultValue(CExecPlan.Make(&c_exec_context))
+ vector[CDeclaration] c_decls
+ vector[CExecNode*] _empty
+ vector[CExecNode*] c_final_node_vec
+ CExecNode *c_node
+ CTable* c_table
+ shared_ptr[CTable] c_out_table
+ shared_ptr[CSourceNodeOptions] c_sourceopts
+ shared_ptr[CSinkNodeOptions] c_sinkopts
+ shared_ptr[CAsyncExecBatchGenerator] c_asyncexecbatchgen
+ shared_ptr[CRecordBatchReader] c_recordbatchreader
+ vector[CDeclaration].iterator plan_iter
+
+ plan_iter = plan.begin()
+
+ # Create source nodes for each input
+ for ipt in inputs:
+ if isinstance(ipt, Table):
+ c_in_table = pyarrow_unwrap_table(ipt).get()
+ c_sourceopts = GetResultValue(
+ CSourceNodeOptions.FromTable(deref(c_in_table), c_exec_context.executor()))
+ else:
+ raise TypeError("Unsupproted type")
+
+ if plan_iter != plan.end():
+ # Flag the source as the input of the first plan node.
+ deref(plan_iter).inputs.push_back(CDeclaration.Input(
+ CDeclaration(tobytes("source"), deref(c_sourceopts))
+ ))
+ else:
+ # Empty plan, make the source the first plan node.
+ c_decls.push_back(
+ CDeclaration(tobytes("source"), deref(c_sourceopts))
+ )
+
+ # Add Here additional nodes
+ while plan_iter != plan.end():
+ c_decls.push_back(deref(plan_iter))
+ inc(plan_iter)
+
+ # Add all CDeclarations to the plan
+ c_node = GetResultValue(
+ CDeclaration.Sequence(c_decls).AddToPlan(&deref(c_exec_plan))
+ )
+ c_final_node_vec.push_back(c_node)
+
+ # Create the output node
+ c_asyncexecbatchgen = make_shared[CAsyncExecBatchGenerator]()
+ c_sinkopts = make_shared[CSinkNodeOptions](c_asyncexecbatchgen.get())
+ GetResultValue(
+ MakeExecNode(tobytes("sink"), &deref(c_exec_plan),
+ c_final_node_vec, deref(c_sinkopts))
+ )
+
+ # Convert the asyncgenerator to a sync batch reader
+ c_recordbatchreader = MakeGeneratorReader(c_node.output_schema(),
+ deref(c_asyncexecbatchgen),
+ c_exec_context.memory_pool())
+
+ # Start execution of the ExecPlan
+ deref(c_exec_plan).Validate()
+ deref(c_exec_plan).StartProducing()
+
+ # Convert output to the expected one.
+ if output_type == Table:
+ c_out_table = GetResultValue(
+ CTable.FromRecordBatchReader(c_recordbatchreader.get()))
+ output = pyarrow_wrap_table(c_out_table)
+ else:
+ raise TypeError("Unsupported output type")
+
+ deref(c_exec_plan).StopProducing()
+
+ return output
+
+
+def tables_join(join_type, left_table, left_keys, right_table, right_keys):
+ """
+ Perform join of two tables.
+
+ The result will be an output table with the result of the join operation
+
+ Parameters
+ ----------
+ join_type : str
+ One of supported join types.
+ left_table : Table
+ The left table for the join operation
+ left_keys : str or list[str]
+ The left table key (or keys) on which the join operation should be performed
+ right_table : Table
+ The right table for the join operation
+ right_keys : str or list[str]
+ The right table key (or keys) on which the join operation should be performed
+
+ Returns
+ -------
+ result_table : Table
+ """
+ cdef:
+ vector[CFieldRef] c_left_keys
+ vector[CFieldRef] c_right_keys
+ vector[CDeclaration] c_decl_plan
+ CJoinType c_join_type
+
+ # Prepare left and right tables Keys to send them to the C++ function
+ if isinstance(left_keys, str):
+ left_keys = [left_keys]
+ for key in left_keys:
+ c_left_keys.push_back(CFieldRef(<c_string>tobytes(key)))
+
+ if isinstance(right_keys, str):
+ right_keys = [right_keys]
+ for key in right_keys:
+ c_right_keys.push_back(CFieldRef(<c_string>tobytes(key)))
+
+ # Pick the join type
+ if join_type == "left semi":
+ c_join_type = CJoinType_LEFT_SEMI
+ elif join_type == "right semi":
+ c_join_type = CJoinType_RIGHT_SEMI
+ elif join_type == "left anti":
+ c_join_type = CJoinType_LEFT_ANTI
+ elif join_type == "right anti":
+ c_join_type = CJoinType_RIGHT_ANTI
+ elif join_type == "inner":
+ c_join_type = CJoinType_INNER
+ elif join_type == "left outer":
+ c_join_type = CJoinType_LEFT_OUTER
+ elif join_type == "right outer":
+ c_join_type = CJoinType_RIGHT_OUTER
+ elif join_type == "full outer":
+ c_join_type = CJoinType_FULL_OUTER
+ else:
+ raise ValueError("Unsupporter join type")
Review comment:
```suggestion
raise ValueError("Unsupported join type")
```
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
+ """
+ Internal Function to create and ExecPlan and run it.
+
+ Parameters
+ ----------
+ inputs : list of Table or Dataset
+ The sources from which the ExecPlan should fetch data.
+ In most cases this is only one, unless the first node of the
+ plan is able to get data from multiple different sources.
+ output_type : Table or Dataset
+ In which format the output should be provided.
+ plan : vector[CDeclaration]
+ The nodes of the plan that should be applied to the sources
+ to produce the output.
+ """
+ cdef:
+ CExecContext c_exec_context = CExecContext(c_default_memory_pool(),
+ GetCpuThreadPool())
+ shared_ptr[CExecPlan] c_exec_plan = GetResultValue(CExecPlan.Make(&c_exec_context))
+ vector[CDeclaration] c_decls
+ vector[CExecNode*] _empty
+ vector[CExecNode*] c_final_node_vec
+ CExecNode *c_node
+ CTable* c_table
+ shared_ptr[CTable] c_out_table
+ shared_ptr[CSourceNodeOptions] c_sourceopts
+ shared_ptr[CSinkNodeOptions] c_sinkopts
+ shared_ptr[CAsyncExecBatchGenerator] c_asyncexecbatchgen
+ shared_ptr[CRecordBatchReader] c_recordbatchreader
+ vector[CDeclaration].iterator plan_iter
+
+ plan_iter = plan.begin()
+
+ # Create source nodes for each input
+ for ipt in inputs:
+ if isinstance(ipt, Table):
+ c_in_table = pyarrow_unwrap_table(ipt).get()
+ c_sourceopts = GetResultValue(
+ CSourceNodeOptions.FromTable(deref(c_in_table), c_exec_context.executor()))
+ else:
+ raise TypeError("Unsupproted type")
Review comment:
```suggestion
raise TypeError("Unsupported type")
```
##########
File path: python/pyarrow/_exec_plan.pyx
##########
@@ -0,0 +1,199 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+# ---------------------------------------------------------------------
+# Implement Internal ExecPlan bindings
+
+# cython: profile=False
+# distutils: language = c++
+# cython: language_level = 3
+
+from cython.operator cimport dereference as deref, preincrement as inc
+
+from pyarrow.includes.common cimport *
+from pyarrow.includes.libarrow cimport *
+from pyarrow.lib cimport (Table, pyarrow_unwrap_table, pyarrow_wrap_table)
+from pyarrow.lib import tobytes
+
+
+cdef execplan(inputs, output_type, vector[CDeclaration] plan):
Review comment:
Longer term, I think the question is to what extent we want to factor out this `execplan` function in a "nicer" interface (even for cython), eg class based, or .. But I suppose for this PR itself it is good enough.
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