SheetReader DuckDB extension

sheetreader is a DuckDB extension that allows reading XLSX files into DuckDB tables with SheetReader, our blazingly fast XLSX parser (https://github.com/polydbms/sheetreader-core).

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This repository is based on https://github.com/duckdb/extension-template.

Table of Contents

• SheetReader DuckDB extension
  • Table of Contents
  • Usage
    • Parameters
  • More information on SheetReader
  • Benchmarks
  • Building yourself
    • Running the extension

Usage

Before using SheetReader, you need to install it from the community extensions and load it into your DuckDB-environment:

INSTALL sheetreader FROM community;
LOAD sheetreader;

Now, you can run your first query:

D SELECT *
  FROM sheetreader('test.xlsx');

The sheetreader() function offers further parameters to load the XLSX-file as required:

D CREATE TABLE test AS FROM sheetreader(
    'test.xlsx',
    sheet_index=1,
    threads=16,
    skip_rows=0,
    has_header=TRUE,
    types=[BOOLEAN,VARCHAR],
    coerce_to_string=TRUE,
    force_types=TRUE
  );

Parameters

Name	Description	Type	Default
sheet_index	Index of the sheet to read. Starts at 1.	INTEGER	1
sheet_name	Name of the sheet to read. Only either sheet_index or sheet_name can be set.	VARCHAR	""
threads	Number of threads to use, while parsing	INTEGER	Half of available cores; minimum 1
skip_rows	Number of rows to skip	INTEGER	0
types	List of types for all columns Types currently available: VARCHAR,BOOLEAN,DOUBLE, DATE. Useful in combination with coerce_to_string and force_types.	LIST(VARCHAR)	Uses types determined by first & second row (after skipped rows)
coerce_to_string	Coerce all cells in column of type VARCHAR to string (i.e. VARCHAR).	BOOLEAN	false
force_types	Use types even if they are not compatible with types determined by first/second row. Cells, that are not of the column type, are set to NULL or coerced to string, if option is set.	BOOLEAN	false
has_header	If set to true: Force to treat first row as header row (only works if all cells are of type VARCHAR). If successful, the cell contents are used for column names. Will overwrite the default behavior, which doesn't use the first row as headers, if all columns have type VARCHAR. If set to false: The extension will still try to treat the first row as header row. The difference is that it will not fail, if the first row is not usable (i.e. not all cells are of type VARCHAR). The first row won't be used as headers, if all columns have type VARCHAR.	BOOLEAN	false

More information on SheetReader

SheetReader was published in the Information Systems Journal.

@article{DBLP:journals/is/GavriilidisHZM23,
  author       = {Haralampos Gavriilidis and
                  Felix Henze and
                  Eleni Tzirita Zacharatou and
                  Volker Markl},
  title        = {SheetReader: Efficient Specialized Spreadsheet Parsing},
  journal      = {Inf. Syst.},
  volume       = {115},
  pages        = {102183},
  year         = {2023},
  url          = {https://doi.org/10.1016/j.is.2023.102183},
  doi          = {10.1016/J.IS.2023.102183},
  timestamp    = {Mon, 26 Jun 2023 20:54:32 +0200},
  biburl       = {https://dblp.org/rec/journals/is/GavriilidisHZM23.bib},
  bibsource    = {dblp computer science bibliography, https://dblp.org}
}

Benchmarks

You can find benchmarks in the above-mentioned paper, comparing SheetReader to other XLSX parsers.

Here is a plot of preliminary benchmarks comparing the sheetreader DuckDB extension to the spatial extension's st_read function:

(System info: 2x Intel(R) Xeon(R) E5530 @ 2.40GHz, 47GiB RAM)

Building yourself

First, clone this repository with the --recurse-submodules flag --- so you get all the needed source files.

To build the extension, run:

GEN=ninja make

The main binaries that will be built are:

./build/release/duckdb
./build/release/extension/sheetreader/sheetreader.duckdb_extension

• duckdb is the binary for the DuckDB shell with the extension code automatically loaded.
• sheetreader.duckdb_extension is the loadable binary as it would be distributed.

Running the extension

To run the self-built extension code, simply start the shell with ./build/release/duckdb.