sqlite-utils insert blah.db blah myfile.txt --all --convert '{"item": s for s in value["all"].split("-")}'

% sqlite-utils insert --help
Usage: sqlite-utils insert [OPTIONS] PATH TABLE JSON_FILE

  Insert records from JSON file into a table, creating the table if it does
  not already exist.

  Input should be a JSON array of objects, unless --nl or --csv is used.

Options:
  --pk TEXT                 Columns to use as the primary key, e.g. id
  --nl                      Expect newline-delimited JSON
  --flatten                 Flatten nested JSON objects
  -c, --csv                 Expect CSV
  --tsv                     Expect TSV
  --convert TEXT            Python code to convert each item
  --import TEXT             Python modules to import
  --delimiter TEXT          Delimiter to use for CSV files
  --quotechar TEXT          Quote character to use for CSV/TSV
  --sniff                   Detect delimiter and quote character
  --no-headers              CSV file has no header row
  --batch-size INTEGER      Commit every X records
  --alter                   Alter existing table to add any missing columns
  --not-null TEXT           Columns that should be created as NOT NULL
  --default <TEXT TEXT>...  Default value that should be set for a column
  --encoding TEXT           Character encoding for input, defaults to utf-8
  -d, --detect-types        Detect types for columns in CSV/TSV data
  --load-extension TEXT     SQLite extensions to load
  --silent                  Do not show progress bar
  --ignore                  Ignore records if pk already exists
  --replace                 Replace records if pk already exists
  --truncate                Truncate table before inserting records, if table
                            already exists
  -h, --help                Show this message and exit.

Usage: sqlite-utils insert [OPTIONS] PATH TABLE FILE

  Insert records from FILE into a table, creating the table if it does not
  already exist.

  By default the input is expected to be a JSON array of objects. Or:

  - Use --nl for newline-delimited JSON objects
  - Use --csv or --tsv for comma-separated or tab-separated input
  - Use --lines to write each incoming line to a column called "line"
  - Use --all to write the entire input to a column called "all"

  You can also use --convert to pass a fragment of Python code that will be
  used to convert each input.

  Your Python code will be passed a "row" variable representing the imported
  row, and can return a modified row.

  If you are using --lines your code will be passed a "line" variable, and for
  --all an "all" variable.

Options:
  --pk TEXT                 Columns to use as the primary key, e.g. id
  --flatten                 Flatten nested JSON objects, so {"a": {"b": 1}}
                            becomes {"a_b": 1}
  --nl                      Expect newline-delimited JSON
  -c, --csv                 Expect CSV input
  --tsv                     Expect TSV input
  --lines                   Treat each line as a single value called 'line'
  --all                     Treat input as a single value called 'all'
  --convert TEXT            Python code to convert each item
  --import TEXT             Python modules to import
  --delimiter TEXT          Delimiter to use for CSV files
  --quotechar TEXT          Quote character to use for CSV/TSV
  --sniff                   Detect delimiter and quote character
  --no-headers              CSV file has no header row
  --batch-size INTEGER      Commit every X records
  --alter                   Alter existing table to add any missing columns
  --not-null TEXT           Columns that should be created as NOT NULL
  --default <TEXT TEXT>...  Default value that should be set for a column
  --encoding TEXT           Character encoding for input, defaults to utf-8
  -d, --detect-types        Detect types for columns in CSV/TSV data
  --load-extension TEXT     SQLite extensions to load
  --silent                  Do not show progress bar
  --ignore                  Ignore records if pk already exists
  --replace                 Replace records if pk already exists
  --truncate                Truncate table before inserting records, if table
                            already exists
  -h, --help                Show this message and exit.