feat(mysql): parse ALTER TABLE AUTO_INCREMENT. (#7520)

MySQL allows setting the auto-increment counter on an existing table.
The property parser already existed for `CREATE TABLE`; this wires it
into `ALTER TABLE` as well.

Author: burnison

sqlglot/parsers/mysql.py

@@ -253,6 +253,7 @@ class MySQLParser(parser.Parser):
     ALTER_PARSERS = {
         **parser.Parser.ALTER_PARSERS,
         "MODIFY": lambda self: self._parse_alter_table_alter(),
+        "AUTO_INCREMENT": lambda self: self._parse_property_assignment(exp.AutoIncrementProperty),
     }
 
     ALTER_ALTER_PARSERS = {

tests/dialects/test_mysql.py

@@ -34,6 +34,7 @@ def test_ddl(self):
         self.validate_identity("ALTER TABLE t ADD INDEX `i` (`c`)")
         self.validate_identity("ALTER TABLE t ADD UNIQUE `i` (`c`)")
         self.validate_identity("ALTER TABLE test_table MODIFY COLUMN test_column LONGTEXT")
+        self.validate_identity("ALTER TABLE t AUTO_INCREMENT=3000000000")
         self.validate_identity("ALTER VIEW v AS SELECT a, b, c, d FROM foo")
         self.validate_identity("ALTER VIEW v AS SELECT * FROM foo WHERE c > 100")
         self.validate_identity(
@@ -1694,3 +1695,9 @@ def test_invisible_column(self):
 
         expr = self.parse_one("ALTER TABLE t ADD COLUMN c INT INVISIBLE")
         self.assertIsNotNone(expr.find(exp.InvisibleColumnConstraint))
+
+    def test_alter_table_auto_increment(self):
+        prop = self.parse_one("ALTER TABLE t AUTO_INCREMENT=3000000000").find(
+            exp.AutoIncrementProperty
+        )
+        self.assertEqual(prop.this.to_py(), 3000000000)