diff --git a/mack/__init__.py b/mack/__init__.py
index 7c6fa49..12c3659 100644
--- a/mack/__init__.py
+++ b/mack/__init__.py
@@ -394,3 +394,33 @@ def with_md5_cols(
     if type(df) == DeltaTable:
         df = df.toDF()
     return df.withColumn(output_col_name, md5(concat_ws("||", *cols)))
+
+
+def check_data(
+    df: Union[DeltaTable, DataFrame],
+    check_invariants: Union[str, List[str]]
+):
+    condition = None
+    if type(df) == DeltaTable:
+        df = df.toDF()
+    if type(check_invariants) == str:
+        condition = check_invariants
+    elif type(check_invariants) == list:
+        check_invariants = ["(" + i + ")" for i in check_invariants]
+        condition = " AND ".join(check_invariants)
+    print(f"For the specified check invariant(s) '{condition}' {df.filter(condition).count()} rows are being affected.")
+    return df.filter(condition)
+
+
+def drop_by_invariants(
+    dt: DeltaTable,
+    delete_invariants: Union[str, List[str]]
+):
+    condition = None
+    if type(delete_invariants) == str:
+        condition = delete_invariants
+    elif type(delete_invariants) == list:
+        delete_invariants = ["(" + i + ")" for i in delete_invariants]
+        condition = " AND ".join(delete_invariants)
+    print(f"{dt.toDF().filter(condition).count()} rows are being deleted from the delta table.")
+    dt.delete(condition)