sql_mode=ORACLE: Add support for database qualified sequence names in NEXTVAL and CURRVAL

SET sql_mode=ORACLE;

DROP SEQUENCE IF EXISTS s1;

CREATE SEQUENCE s1;

SELECT NEXT VALUE FOR s1;

SELECT s1.nextval;

+-------------------+

| NEXT VALUE FOR s1 |

+-------------------+

|                 1 |

+-------------------+

+------------+

| s1.nextval |

+------------+

|          2 |

+------------+

SELECT NEXT VALUE FOR test.s1;

+------------------------+

| NEXT VALUE FOR test.s1 |

+------------------------+

|                      3 |

+------------------------+

SELECT PREVIOUS VALUE FOR test.s1;

+----------------------------+

| PREVIOUS VALUE FOR test.s1 |

+----------------------------+

|                          3 |

+----------------------------+

SELECT test.s1.nextval;

SELECT test.s1.currval;