## has_rows() Check whether a table has a certain number of rows. Usage ``` python has_rows( count=None, *, min=None, max=None, ) ``` The [has_rows()](has_rows.md#pointblank.has_rows) function returns a callable that, when given a table, checks whether the row count satisfies a specified condition. It is designed for use with the `active=` parameter of validation methods so that a validation step can be conditionally skipped when the target table is too small, too large, or empty. The callable supports several modes: - **exact count**: `has_rows(count=N)` returns `True` only if the table has exactly `N` rows. - **minimum**: `has_rows(min=N)` returns `True` if the table has at least `N` rows. - **maximum**: `has_rows(max=N)` returns `True` if the table has at most `N` rows. - **range**: `has_rows(min=A, max=B)` returns `True` if the row count falls within `[A, B]`. - **non-empty**: [has_rows()](has_rows.md#pointblank.has_rows) (no arguments) returns `True` if the table has at least one row. A note is attached to any skipped step in the validation report explaining the row count condition that was not met. The callable is evaluated against the original table *before* any `pre=` processing is applied. This means the column check is performed on the raw input data, not on a pre-processed version of it. ## Parameters `count: int | None = None` The exact number of rows the table should have. Cannot be used together with `min=` or `max=`. `min: int | None = None` The minimum number of rows (inclusive) the table should have. Can be used alone or with `max=`. `max: int | None = None` The maximum number of rows (inclusive) the table should have. Can be used alone or with `min=`. ## Returns `Callable[[Any], bool]` A callable that accepts a table and returns `True` if the row count satisfies the specified condition, `False` otherwise. When the callable returns `False`, it stores diagnostic information that is used to generate a descriptive note in the validation report. ## How It Works When interrogate() is called, each validation step whose `active=` parameter is a callable will have that callable evaluated with the target table. If the callable returns `False`, the step is deactivated and an explanatory note is added to the validation report. The note is locale-aware: if the Validate object was created with a non-English `locale=`, the note will be translated accordingly. ## Examples Skip a validation step if the table is empty: ``` python import pointblank as pb import polars as pl tbl = pl.DataFrame({"x": [1, 2, 3]}) empty_tbl = pl.DataFrame({"x": []}) validation = ( pb.Validate(data=empty_tbl) .col_vals_gt(columns="x", value=0, active=pb.has_rows()) .interrogate() ) validation ```

		STEP	COLUMNS	VALUES	TBL	EVAL	UNITS	PASS	FAIL	W	E	C	EXT
#4CA64C66	1	col_vals_gt()	x	0		--	--	--	--	--	--	--	--
Notes Step 1 (active_check) Step skipped -- Row count check failed: table is empty.

The step was skipped because the table has no rows. Only run a step when the table has at least a minimum number of rows: ``` python validation = ( pb.Validate(data=tbl) .col_vals_gt(columns="x", value=0, active=pb.has_rows(min=100)) .interrogate() ) validation ```

		STEP	COLUMNS	VALUES	TBL	EVAL	UNITS	PASS	FAIL	W	E	C	EXT
#4CA64C66	1	col_vals_gt()	x	0		--	--	--	--	--	--	--	--
Notes Step 1 (active_check) Step skipped -- Row count check failed: expected at least `100` row(s), found `3`.

The step was skipped because the table has only 3 rows, which is fewer than the required minimum of `100`. You can also check for an exact count or a range: ``` python validation = ( pb.Validate(data=tbl) .col_vals_gt(columns="x", value=0, active=pb.has_rows(count=3)) .col_vals_gt(columns="x", value=0, active=pb.has_rows(min=2, max=10)) .col_vals_gt(columns="x", value=0, active=pb.has_rows(count=100)) .interrogate() ) validation ```

		STEP	COLUMNS	VALUES	EVAL	UNITS	PASS	FAIL	W	E	C	EXT
#4CA64C	1	col_vals_gt()	x	0	✓	3	3 1.00	0 0.00	--	--	--	--
#4CA64C	2	col_vals_gt()	x	0	✓	3	3 1.00	0 0.00	--	--	--	--
#4CA64C66	3	col_vals_gt()	x	0	--	--	--	--	--	--	--	--
Notes Step 3 (active_check) Step skipped -- Row count check failed: expected exactly `100` row(s), found `3`.

The first two steps ran because the table has exactly 3 rows (matching `count=3`) and falls within the range `[2, 10]`. The third step was skipped because `3` does not equal `100`.