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[R] Allow all file writers to write from a RecordBatchReader #30887

Closed as not planned
Closed as not planned
[R] Allow all file writers to write from a RecordBatchReader#30887
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Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement

Description

@asfimport
asfimport
opened on Jan 21, 2022

After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).

There is a workaround (at least for Parquet), but it's quite verbose:

tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE

Reporter: Dewey Dunnington / @paleolimbot

Related issues:

Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.

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[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
      Skip to content
      [R] Allow all file writers to write from a RecordBatchReader #30887
      Closed as not planned
      Closed as not planned
      [R] Allow all file writers to write from a RecordBatchReader#30887
      Labels
      Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
      Description
      @asfimport
      asfimport
      opened on Jan 21, 2022
      After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
      There is a workaround (at least for Parquet), but it's quite verbose:
      tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
      Reporter: Dewey Dunnington / @paleolimbot
      Related issues:
      Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
      Metadata
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try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
          Skip to content
          [R] Allow all file writers to write from a RecordBatchReader #30887
          Closed as not planned
          Closed as not planned
          [R] Allow all file writers to write from a RecordBatchReader#30887
          Labels
          Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
          Description
          @asfimport
          asfimport
          opened on Jan 21, 2022
          After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
          There is a workaround (at least for Parquet), but it's quite verbose:
          tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
          Reporter: Dewey Dunnington / @paleolimbot
          Related issues:
          Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
              Skip to content
              [R] Allow all file writers to write from a RecordBatchReader #30887
              Closed as not planned
              Closed as not planned
              [R] Allow all file writers to write from a RecordBatchReader#30887
              Labels
              Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
              Description
              @asfimport
              asfimport
              opened on Jan 21, 2022
              After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
              There is a workaround (at least for Parquet), but it's quite verbose:
              tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
              Reporter: Dewey Dunnington / @paleolimbot
              Related issues:
              Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
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, 'i');
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try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
                  Skip to content
                  [R] Allow all file writers to write from a RecordBatchReader #30887
                  Closed as not planned
                  Closed as not planned
                  [R] Allow all file writers to write from a RecordBatchReader#30887
                  Labels
                  Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
                  Description
                  @asfimport
                  asfimport
                  opened on Jan 21, 2022
                  After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
                  There is a workaround (at least for Parquet), but it's quite verbose:
                  tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
                  Reporter: Dewey Dunnington / @paleolimbot
                  Related issues:
                  Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
                  Metadata
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                    Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
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                      None yet
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
                      Skip to content
                      [R] Allow all file writers to write from a RecordBatchReader #30887
                      Closed as not planned
                      Closed as not planned
                      [R] Allow all file writers to write from a RecordBatchReader#30887
                      Labels
                      Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
                      Description
                      @asfimport
                      asfimport
                      opened on Jan 21, 2022
                      After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
                      There is a workaround (at least for Parquet), but it's quite verbose:
                      tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
                      Reporter: Dewey Dunnington / @paleolimbot
                      Related issues:
                      Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
                        Type
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                        No projects
                          Milestone
                          No milestone
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, 'i');
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
                          Skip to content
                          [R] Allow all file writers to write from a RecordBatchReader #30887
                          Closed as not planned
                          Closed as not planned
                          [R] Allow all file writers to write from a RecordBatchReader#30887
                          Labels
                          Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
                          Description
                          @asfimport
                          asfimport
                          opened on Jan 21, 2022
                          After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
                          There is a workaround (at least for Parquet), but it's quite verbose:
                          tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
                          Reporter: Dewey Dunnington / @paleolimbot
                          Related issues:
                          Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
[R] Allow all file writers to write from a RecordBatchReader · Issue #30887 · apache/arrow · GitHub
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                              [R] Allow all file writers to write from a RecordBatchReader #30887
                              Closed as not planned
                              Closed as not planned
                              [R] Allow all file writers to write from a RecordBatchReader#30887
                              Labels
                              Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
                              Description
                              @asfimport
                              asfimport
                              opened on Jan 21, 2022
                              After ARROW-15040 we will be able to use a RecordBatchReader as input to a CSV file writer. It would be similarly helpful to be able to use a RecordBatchReader as input to write Parquet, IPC, and Feather files. The RecordBatchReader is important because it can be imported from C/Python/database results (e.g., DuckDB).
                              There is a workaround (at least for Parquet), but it's quite verbose:
                              tf<- tempfile(fileext=".parquet")
df<-data.frame(a=1:1e6)
arrow::write_parquet(df, tf)
dbdir<-":memory:"sink<- tempfile(fileext=".parquet")
con<-DBI::dbConnect(duckdb::duckdb(dbdir=dbdir))
res<-DBI::dbSendQuery(con, glue::glue_sql("SELECT * FROM { tf }", .con=con), arrow=TRUE)
reader<-duckdb::duckdb_fetch_record_batch(res)
# write_parquet() doesn't *quite* support a record batch reader yet# and we want to stream to the writer to support possibly# bigger-than-memory resultsfs<-arrow::LocalFileSystem$create()
stream<-fs$OpenOutputStream(sink)
chunk_size<- asNamespace("arrow")$calculate_chunk_size(1e6, 1)
batch<-arrow::Table$create(reader$read_next_batch())
writer<-arrow::ParquetFileWriter$create(
reader$schema,
stream,
properties=arrow::ParquetWriterProperties$create(batch)
)
writer$WriteTable(batch, chunk_size=chunk_size)
while (!is.null(batch<-reader$read_next_batch())) {
writer$WriteTable(arrow::Table$create(batch), chunk_size=chunk_size)
}
writer$Close()
stream$close()
DBI::dbDisconnect(con, shutdown=TRUE)
df2<-dplyr::arrange(arrow::read_parquet(sink), a)
identical(df2$a, df$a)
#> [1] TRUE
                              Reporter: Dewey Dunnington / @paleolimbot
                              Related issues:
                              Note: This issue was originally created as ARROW-15405. Please see the migration documentation for further details.
                              Metadata
                              Metadata
                              Assignees
                              No one assigned
                                Labels
                                Component: RStatus: stale-warningIssues and PRs flagged as stale which are due to be closed if no indication otherwiseType: enhancement
                                Type
                                No type
                                Projects
                                No projects
                                  Milestone
                                  No milestone
                                  Relationships
                                  None yet
                                  Development
                                  No branches or pull requests
                                  Issue actions