Tests for analyze tables

This commit is contained in:
Simon Willison 2020-12-12 20:46:13 -08:00
commit f7efe77ccb
2 changed files with 103 additions and 3 deletions

View file

@ -1361,7 +1361,14 @@ def insert_files(
required=True,
)
@click.argument("tables", nargs=-1)
@click.option("-c", "--column", "columns", type=str, multiple=True, help="Specific columns to analyze")
@click.option(
"-c",
"--column",
"columns",
type=str,
multiple=True,
help="Specific columns to analyze",
)
@click.option("--save", is_flag=True, help="Save results to _analyze_tables table")
@load_extension_option
def analyze_tables(
@ -1381,11 +1388,13 @@ def analyze_tables(
for table in tables:
table_counts[table] = db[table].count
for column in db[table].columns:
if (not columns or column.name in columns):
if not columns or column.name in columns:
todo.append((table, column.name))
# Now we now how many we need to do
for i, (table, column) in enumerate(todo):
column_details = db[table].analyze_column(column, total_rows=table_counts[table])
column_details = db[table].analyze_column(
column, total_rows=table_counts[table]
)
if save:
db["_analyze_tables"].insert(
column_details._asdict(), pk=("table", "column"), replace=True

View file

@ -0,0 +1,91 @@
from sqlite_utils.db import ForeignKey, ColumnDetails
from sqlite_utils import cli
from sqlite_utils.utils import OperationalError
from click.testing import CliRunner
import pytest
import sqlite3
import textwrap
@pytest.fixture
def db_to_analyze(fresh_db):
stuff = fresh_db["stuff"]
stuff.insert_all(
[
{"id": 1, "owner": "Terry", "size": 5},
{"id": 2, "owner": "Joan", "size": 4},
{"id": 3, "owner": "Kumar", "size": 5},
{"id": 4, "owner": "Anne", "size": 5},
{"id": 5, "owner": "Terry", "size": 5},
{"id": 6, "owner": "Joan", "size": 4},
{"id": 7, "owner": "Kumar", "size": 5},
{"id": 8, "owner": "Joan", "size": 4},
],
pk="id",
)
return fresh_db
@pytest.mark.parametrize(
"column,expected",
[
(
"id",
ColumnDetails(
table="stuff",
column="id",
total_rows=8,
num_null=0,
num_blank=0,
num_distinct=8,
most_common=None,
least_common=None,
),
),
(
"owner",
ColumnDetails(
table="stuff",
column="owner",
total_rows=8,
num_null=0,
num_blank=0,
num_distinct=4,
most_common=[("Joan", 3), ("Terry", 2)],
least_common=[("Anne", 1), ("Kumar", 2)],
),
),
(
"size",
ColumnDetails(
table="stuff",
column="size",
total_rows=8,
num_null=0,
num_blank=0,
num_distinct=2,
most_common=[(5, 5), (4, 3)],
least_common=None,
),
),
],
)
def test_analyze_column(db_to_analyze, column, expected):
assert db_to_analyze["stuff"].analyze_column(column, common_limit=2) == expected
def test_analyze_table(db_to_analyze, tmpdir):
path = str(tmpdir / "test.db")
db = sqlite3.connect(path)
db.executescript("\n".join(db_to_analyze.conn.iterdump()))
result = CliRunner().invoke(cli.cli, ["analyze-tables", path])
assert (
result.output.strip()
== textwrap.dedent(
"""
1/3: ColumnDetails(table='stuff', column='id', total_rows=8, num_null=0, num_blank=0, num_distinct=8, most_common=None, least_common=None)
2/3: ColumnDetails(table='stuff', column='owner', total_rows=8, num_null=0, num_blank=0, num_distinct=4, most_common=[('Joan', 3), ('Terry', 2), ('Kumar', 2), ('Anne', 1)], least_common=None)
3/3: ColumnDetails(table='stuff', column='size', total_rows=8, num_null=0, num_blank=0, num_distinct=2, most_common=[(5, 5), (4, 3)], least_common=None)
"""
).strip()
)