Remove typo in _exec_drop_col_fk_constraint

Fixed issue where the ``mssql_drop_foreign_key=True`` flag on
``op.drop_column`` would lead to incorrect syntax error due to a typo in the
SQL emitted, same typo was present in the test as well so it was not
detected. Pull request courtesy Oleg Shigorin.

Fixes: #716
Closes: #717
Pull-request: #717
Pull-request-sha: dcd90fb

Change-Id: I022a66a3bcebf689945cfbd36bed0ebed248364f

alembic/ddl/mssql.py

@@ -205,7 +205,7 @@ def _exec_drop_col_fk_constraint(element, compiler, **kw):
 sys.foreign_keys fk join sys.foreign_key_columns fkc
 on fk.object_id=fkc.constraint_object_id
 where fkc.parent_object_id = object_id('%(schema_dot)s%(tname)s')
-`and col_name(fkc.parent_object_id, fkc.parent_column_id) = '%(colname)s'
+and col_name(fkc.parent_object_id, fkc.parent_column_id) = '%(colname)s'
 exec('alter table %(tname_quoted)s drop constraint ' + @const_name)""" % {
         "tname": tname,
         "colname": colname,

docs/build/unreleased/716.rst

@@ -0,0 +1,8 @@
+.. change::
+   :tags: bug, mssql
+   :tickets: 716
+
+   Fixed issue where the ``mssql_drop_foreign_key=True`` flag on
+   ``op.drop_column`` would lead to incorrect syntax error due to a typo in the
+   SQL emitted, same typo was present in the test as well so it was not
+   detected. Pull request courtesy Oleg Shigorin.

tests/test_mssql.py

@@ -191,7 +191,7 @@ def test_drop_column_w_fk(self):
             "select @const_name = [name] from\n"
             "sys.foreign_keys fk join sys.foreign_key_columns fkcon "
             "fk.object_id=fkc.constraint_object_id\n"
-            "where fkc.parent_object_id = object_id('t1')`and "
+            "where fkc.parent_object_id = object_id('t1')\nand "
             "col_name(fkc.parent_object_id, fkc.parent_column_id) = 'c1'\n"
             "exec('alter table t1 drop constraint ' + @const_name)"
         )
@@ -208,7 +208,7 @@ def test_drop_column_w_fk_schema(self):
             "select @const_name = [name] from\n"
             "sys.foreign_keys fk join sys.foreign_key_columns fkcon "
             "fk.object_id=fkc.constraint_object_id\n"
-            "where fkc.parent_object_id = object_id('xyz.t1')`and "
+            "where fkc.parent_object_id = object_id('xyz.t1')\nand "
             "col_name(fkc.parent_object_id, fkc.parent_column_id) = 'c1'\n"
             "exec('alter table xyz.t1 drop constraint ' + @const_name)"
         )