csvs-to-sqlite

Convert CSV files into a SQLite database. Browse and publish that SQLite database with Datasette.

Basic usage:

csvs-to-sqlite myfile.csv mydatabase.db

This will create a new SQLite database called mydatabase.db containing a single table, myfile, containing the CSV content.

You can provide multiple CSV files:

csvs-to-sqlite one.csv two.csv bundle.db

The bundle.db database will contain two tables, one and two.

This means you can use wildcards:

csvs-to-sqlite ~/Downloads/*.csv my-downloads.db

If you pass a path to one or more directories, the script will recursively search those directories for CSV files and create tables for each one.

csvs-to-sqlite ~/path/to/directory all-my-csvs.db

Handling TSV (tab-separated values)

You can use the -s option to specify a different delimiter. If you want to use a tab character you'll need to apply shell escaping like so:

csvs-to-sqlite my-file.tsv my-file.db -s $'\t'

Refactoring columns into separate lookup tables

Let's say you have a CSV file that looks like this:

county,precinct,office,district,party,candidate,votes
Clark,1,President,,REP,John R. Kasich,5
Clark,2,President,,REP,John R. Kasich,0
Clark,3,President,,REP,John R. Kasich,7

(Real example taken from the Open Elections project)

You can now convert selected columns into separate lookup tables using the new --extract-column option (shortname: -c) - for example:

csvs-to-sqlite openelections-data-*/*.csv \
    -c county:County:name \
    -c precinct:Precinct:name \
    -c office -c district -c party -c candidate \
    openelections.db

The format is as follows:

column_name:optional_table_name:optional_table_value_column_name

If you just specify the column name e.g. -c office, the following table will be created:

CREATE TABLE "office" (
    "id" INTEGER PRIMARY KEY,
    "value" TEXT
);

If you specify all three options, e.g. -c precinct:Precinct:name the table will look like this:

CREATE TABLE "Precinct" (
    "id" INTEGER PRIMARY KEY,
    "name" TEXT
);

The original tables will be created like this:

CREATE TABLE "ca__primary__san_francisco__precinct" (
    "county" INTEGER,
    "precinct" INTEGER,
    "office" INTEGER,
    "district" INTEGER,
    "party" INTEGER,
    "candidate" INTEGER,
    "votes" INTEGER,
    FOREIGN KEY (county) REFERENCES County(id),
    FOREIGN KEY (party) REFERENCES party(id),
    FOREIGN KEY (precinct) REFERENCES Precinct(id),
    FOREIGN KEY (office) REFERENCES office(id),
    FOREIGN KEY (candidate) REFERENCES candidate(id)
);

They will be populated with IDs that reference the new derived tables.

Installation

$ pip install csvs-to-sqlite

csvs-to-sqlite now requires Python 3. If you are running Python 2 you can install the last version to support Python 2:

$ pip install csvs-to-sqlite==0.9.2

csvs-to-sqlite --help

Usage: csvs-to-sqlite [OPTIONS] PATHS... DBNAME

  PATHS: paths to individual .csv files or to directories containing .csvs

  DBNAME: name of the SQLite database file to create

Options:
  -s, --separator TEXT         Field separator in input .csv
  -q, --quoting INTEGER        Control field quoting behavior per csv.QUOTE_*
                               constants. Use one of QUOTE_MINIMAL (0),
                               QUOTE_ALL (1), QUOTE_NONNUMERIC (2) or
                               QUOTE_NONE (3).
  --skip-errors                Skip lines with too many fields instead of
                               stopping the import
  --replace-tables             Replace tables if they already exist
  -t, --table TEXT             Table to use (instead of using CSV filename)
  -c, --extract-column TEXT    One or more columns to 'extract' into a
                               separate lookup table. If you pass a simple
                               column name that column will be replaced with
                               integer foreign key references to a new table
                               of that name. You can customize the name of the
                               table like so:
                                   state:States:state_name
                               This will pull unique values from the 'state'
                               column and use them to populate a new 'States'
                               table, with an id column primary key and a
                               state_name column containing the strings from
                               the original column.
  -d, --date TEXT              One or more columns to parse into ISO formatted
                               dates
  -dt, --datetime TEXT         One or more columns to parse into ISO formatted
                               datetimes
  -df, --datetime-format TEXT  One or more custom date format strings to try
                               when parsing dates/datetimes
  -pk, --primary-key TEXT      One or more columns to use as the primary key
  -f, --fts TEXT               One or more columns to use to populate a full-
                               text index
  -i, --index TEXT             Add index on this column (or a compound index
                               with -i col1,col2)
  --shape TEXT                 Custom shape for the DB table - format is
                               csvcol:dbcol(TYPE),...
  --filename-column TEXT       Add a column with this name and populate with
                               CSV file name
  --no-index-fks               Skip adding index to foreign key columns
                               created using --extract-column (default is to
                               add them)
  --no-fulltext-fks            Skip adding full-text index on values extracted
                               using --extract-column (default is to add them)
  --just-strings               Import all columns as text strings by default
                               (and, if specified, still obey --shape,
                               --date/datetime, and --datetime-format)

  --version                    Show the version and exit.
  --help                       Show this message and exit.