Fix SQL split string to include ;-less statements (#25713)

There was a bug in an incoming change to common-sql provider
introduced in #23971 where `;-less` statements were removed
when "split_statements" flag was used. Since this flag is used
by default in Databricks statement, it introduced backwards
incompatible change.

airflow/providers/common/sql/hooks/sql.py

@@ -244,7 +244,9 @@ def split_sql_string(sql: str) -> List[str]:
         :return: list of individual expressions
         """
         splits = sqlparse.split(sqlparse.format(sql, strip_comments=True))
-        statements = [s.rstrip(';') for s in splits if s.endswith(';')]
+        statements: List[str] = list(
+            filter(None, [s.rstrip(';').strip() if s.endswith(';') else s.strip() for s in splits])
+        )
         return statements
 
     def run(

tests/providers/common/sql/hooks/test_sqlparse.py

@@ -0,0 +1,41 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+import pytest
+
+from airflow.providers.common.sql.hooks.sql import DbApiHook
+
+
+@pytest.mark.parametrize(
+    "line,parsed_statements",
+    [
+        ('SELECT * FROM table', ['SELECT * FROM table']),
+        ('SELECT * FROM table;', ['SELECT * FROM table']),
+        ('SELECT * FROM table; # comment', ['SELECT * FROM table']),
+        ('SELECT * FROM table; # comment;', ['SELECT * FROM table']),
+        (' SELECT * FROM table ; # comment;', ['SELECT * FROM table']),
+        ('SELECT * FROM table;;;;;', ['SELECT * FROM table']),
+        ('SELECT * FROM table;;# comment;;;', ['SELECT * FROM table']),
+        ('SELECT * FROM table;;# comment;; ;', ['SELECT * FROM table']),
+        (
+            'SELECT * FROM table; SELECT * FROM table2 # comment',
+            ['SELECT * FROM table', 'SELECT * FROM table2'],
+        ),
+    ],
+)
+def test_sqlparse(line, parsed_statements):
+    assert DbApiHook.split_sql_string(line) == parsed_statements