查询以根据与电子邮件关联的最新名称检索唯一电子邮件地址

Table Definitions:

表定义：

CREATE TABLE "USERS"
   (    "USER_ID" NUMBER,
    "EMAIL" VARCHAR2(100),
    "GENDER" CHAR(1),
    "AGE" NUMBER,
    "NAME" VARCHAR2(50),
     CONSTRAINT "USERS_PK" PRIMARY KEY ("USER_ID");

 CREATE TABLE "SUBSCRIPTIONS"
   (    "SUBSCRIPTION_ID" NUMBER,
    "USER_ID" NUMBER NOT NULL ENABLE,
    "SUBSCRIPTION_TYPE" VARCHAR2(50),
    "ACTIVE_INDICATOR" VARCHAR2(3),
     CONSTRAINT "SUBS_PK" PRIMARY KEY ("SUBSCRIPTION_ID");

  CREATE TABLE "TRANSACTIONS"
   (    "SUBSCRIPTION_ID" NUMBER,
    "ACTION" VARCHAR2(50),
    "TIMESTAMP" DATE,
     CONSTRAINT "TR_PK" PRIMARY KEY ("SUBSCRIPTION_ID", "ACTION", "TIMESTAMP");
CREATE TABLE "USERS