Fix handling of the ALTER TABLE ... ADD KEY queries (#553)

* Add the test_alter suite (see #542)

* RELEVANT_KEYWORDS: treat the KEY token in the same way as INDEX is treated

Author: macbre

sql_metadata/keywords_lists.py

@@ -125,6 +125,7 @@ class TokenType(str, Enum):
     "RETURNING",
     "VALUES",
     "INDEX",
+    "KEY",
     "WITH",
     "WINDOW",
 }

test/test_alter.py

@@ -0,0 +1,13 @@
+from sql_metadata import Parser, QueryType
+
+
+def test_alter_table_indices_key():
+    parser = Parser("ALTER TABLE foo_table ADD KEY `idx_foo` (`bar`);")
+    assert parser.query_type == QueryType.ALTER
+    assert parser.tables == ["foo_table"]
+
+
+def test_alter_table_indices_index():
+    parser = Parser("ALTER TABLE foo_table ADD INDEX `idx_foo` (`bar`);")
+    assert parser.query_type == QueryType.ALTER
+    assert parser.tables == ["foo_table"]