--no-headers option for sqlite-utils insert --csv, closes #228

docs/cli.rst

@@ -518,6 +518,17 @@ You can import that using::
 
 Passing ``--delimiter``, ``--quotechar`` or ``--sniff`` implies ``--csv``, so you can omit the ``--csv`` option.
 
+.. _cli_insert_csv_tsv_no_header:
+
+CSV files without a header row
+------------------------------
+
+The first row of any CSV or TSV file is expected to contain the names of the columns in that file.
+
+If your file does not include this row, you can use the ``--no-headers`` option to specify that the tool should not use that fist row as headers.
+
+If you do this, the table will be created with column names called ``untitled_1`` and ``untitled_2`` and so on. You can then rename them using the ``sqlite-utils transform ... --rename`` command, see :ref:`cli_transform_table`.
+
 .. _cli_insert_replace:
 
 Insert-replacing data

sqlite_utils/cli.py

@@ -618,6 +618,9 @@ def insert_upsert_options(fn):
             click.option(
                 "--sniff", is_flag=True, help="Detect delimiter and quote character"
             ),
+            click.option(
+                "--no-headers", is_flag=True, help="CSV file has no header row"
+            ),
             click.option(
                 "--batch-size", type=int, default=100, help="Commit every X records"
             ),
@@ -660,6 +663,7 @@ def insert_upsert_implementation(
     delimiter,
     quotechar,
     sniff,
+    no_headers,
     batch_size,
     alter,
     upsert,
@@ -674,7 +678,7 @@ def insert_upsert_implementation(
 ):
     db = sqlite_utils.Database(path)
     _load_extensions(db, load_extension)
-    if delimiter or quotechar or sniff:
+    if delimiter or quotechar or sniff or no_headers:
         csv = True
     if (nl + csv + tsv) >= 2:
         raise click.ClickException("Use just one of --nl, --csv or --tsv")
@@ -699,7 +703,12 @@ def insert_upsert_implementation(
             if quotechar:
                 csv_reader_args["quotechar"] = quotechar
             reader = csv_std.reader(decoded, **csv_reader_args)
-            headers = next(reader)
+            first_row = next(reader)
+            if no_headers:
+                headers = ["untitled_{}".format(i + 1) for i in range(len(first_row))]
+                reader = itertools.chain([first_row], reader)
+            else:
+                headers = first_row
             docs = (dict(zip(headers, row)) for row in reader)
     else:
         try:
@@ -756,6 +765,7 @@ def insert(
     delimiter,
     quotechar,
     sniff,
+    no_headers,
     batch_size,
     alter,
     encoding,
@@ -785,6 +795,7 @@ def insert(
             delimiter,
             quotechar,
             sniff,
+            no_headers,
             batch_size,
             alter=alter,
             upsert=False,
@@ -815,6 +826,7 @@ def upsert(
     delimiter,
     quotechar,
     sniff,
+    no_headers,
     alter,
     not_null,
     default,
@@ -839,6 +851,7 @@ def upsert(
             delimiter,
             quotechar,
             sniff,
+            no_headers,
             batch_size,
             alter=alter,
             upsert=True,

tests/test_cli.py

@@ -1819,3 +1819,39 @@ def test_long_csv_column_value(tmpdir):
     rows = list(db["bigtable"].rows)
     assert len(rows) == 1
     assert rows[0]["text"] == long_string
+
+
+@pytest.mark.parametrize(
+    "args",
+    (
+        ["--csv", "--no-headers"],
+        ["--no-headers"],
+    ),
+)
+def test_csv_import_no_headers(tmpdir, args):
+    db_path = str(tmpdir / "test.db")
+    csv_path = str(tmpdir / "test.csv")
+    csv_file = open(csv_path, "w")
+    csv_file.write("Cleo,Dog,5\n")
+    csv_file.write("Tracy,Spider,7\n")
+    csv_file.close()
+    result = CliRunner().invoke(
+        cli.cli,
+        ["insert", db_path, "creatures", csv_path] + args,
+        catch_exceptions=False,
+    )
+    assert result.exit_code == 0
+    db = Database(db_path)
+    schema = db["creatures"].schema
+    assert schema == (
+        "CREATE TABLE [creatures] (\n"
+        "   [untitled_1] TEXT,\n"
+        "   [untitled_2] TEXT,\n"
+        "   [untitled_3] TEXT\n"
+        ")"
+    )
+    rows = list(db["creatures"].rows)
+    assert rows == [
+        {"untitled_1": "Cleo", "untitled_2": "Dog", "untitled_3": "5"},
+        {"untitled_1": "Tracy", "untitled_2": "Spider", "untitled_3": "7"},
+    ]