DataScan.save_to_json()

Save the profile to a JSON file.

Usage

Source

DataScan.save_to_json(output_file)

Saving a scan to a file is the simplest way to keep a baseline: scan a table once, save the profile, and load it later with load_from_json() to compare a new scan against it with compare(). The file holds the output of to_json(), so it’s small (it stores the statistics, not the data) and can be kept in version control next to the code that produces the table.

Parameters

output_file: str

The path to the output JSON file. An existing file is overwritten.

Returns

None

Nothing is returned. The profile is written to output_file.

Examples

Let’s save a profile of the small_table dataset to a file in a temporary directory.

import pointblank as pb
import tempfile
from pathlib import Path

small_table = pb.load_dataset(dataset="small_table", tbl_type="polars")

profile_path = Path(tempfile.mkdtemp()) / "small_table_profile.json"

pb.DataScan(small_table, tbl_name="small_table").save_to_json(profile_path)

print(profile_path.read_text()[:180])

{
    "metadata": {
        "table_name": "small_table",
        "row_count": 13,
        "columns": [
            "date_time",
            "date",
            "a",
            "b"

The file starts with the table’s metadata, and the column profiles follow. Loading it with load_from_json() gives back the same profile, without needing the table itself.