下面对union的描述正确的是()A.union只连接结果集完全一样的查询语句B.union可以连接结果集中数据类型个数相同的多个结果集C.union是筛选关键词，对结果集再进行操作D.任何查询语句都可以用union来连接

By 1992 the European Union had become a full-fledged A: Economic union B: Monetary union C: Common marcket D: Fiscal union

The Maastricht Treaty of 1991 established a blueprint for economic union and monetary union for European Union members.

At present, the European Union is __________ . A: a free trade area B: a customs union C: a common market D: an economic union

中国大学MOOC: The federal union is a union of people in which ___________.

1. The European Union is best described as a _______________ . A: free trade area B: customs union C: common market D: economic union

As of 1992, the European Union had achieved the monetary union stage of economic integration.

European Union is the political and Economic Union in Europe developed from European Community.

以下共用体定义错误的是（） A: union{ int i;char ch;float f;}a,b,c; B: union data{int i;char ch;float f;} C: union data{int i; char ch;float f;}union data a,b,c; D: union data{ int i;char ch;float f;};union dataa,b,c;

Customs Union