cgtt

CGTT essentially moves the table setup process outside the session .

从本质上说，CGTT将表设置流程移到了会话外部。

There are two major motivations for the creation of CGTT .

创建CGTT主要有两个动机。

Roll back conditions ( CGTT allows flexibility for this )

回滚条件（CGTT具有这方面的灵活性）

Tuning can be made easier with the CGTT support of indexes .

CGTT在支持索引后也简化了调优工作。

CGTT supports import / export , although it does not support load .

CGTT支持导入/导出，但它不支持载入。

CGTT tables can be defined up front , and users can use them much like regular tables .

可以提前定义CGTT表，并且用户可以像普通表一样使用它。

You are able to disable compression of CGTT tables .

您可以禁用压缩CGTT表。

Because there is no locking requirement ( all data is local ), CGTT performs better than regular tables .

由于不需要锁定（所有数据都是本地的），因此CGTT的性能要比普通表更好。

If indexes are created on the CGTT table , the query compiler will take those indexes into account .

如果为CGTT表创建了索引，则查询编译器会将这些索引考虑在内。

So once a CGTT is created , it can be used by any session without having to create it again .

因此，一旦创建了一个CGTT，它可由任何会话使用，没有必要再次创建它。

Compared to CGTT , DGTT has the following limitations

与CGTT相比，DGTT具有以下限制

CGTT does not support constraints .

CGTT不支持约束。

Convert a declared global temporary table ( DGTT ) to a created global temporary table ( CGTT )

将已声明的全局临时表（DGTT）转换为已创建的全局临时表（CGTT）

Once they commit their selections , they are moved from the CGTT to the real tables .

提交选择之后，它们才从CGTT移动到实际表中。

The procedure simply selects from the monitoring table function and inserts the data returned into the CGTT in order to take a baseline .

这个过程对监控表函数执行选择并把返回的数据插入CGTT中以取得基线。

Create a table function that wraps the underlying monitoring table function and takes deltas against the baseline data stored in the CGTT .

创建一个表函数，它包装底层的监控表函数，产生相对于CGTT中存储的基线数据的差值。

Each connection using the CGTT has its own copy of the CGTT and only sees the data in its copy .

使用CGTT的每个连接拥有自己的CGTT拷贝，而且只能看到自己拷贝中的数据。

You can create triggers for CGTT .

您可以为CGTT创建触发器。

The syntax for CGTT is very similar to DGTT .

CGTT的语法与DGTT极为相似。

Use a created global temporary table ( CGTT ) for per-session storage of the baseline data ( use one CGTT per table function ) .

使用为基线数据的每会话存储创建的全局临时表（CGTT）（对于每个表函数，使用一个CGTT）。

Note : If baseline data does not exist in the CGTT , the wrapper function simply returns the data directly from the underlying monitor table function .

注意：如果CGTT中不存在基线数据，包装器函数直接返回底层监控表函数产生的数据。

The second motivation for the CGTT offering is to assist the translations of non-DB2 temporary tables to DB2 temporary tables .

提供CGTT的第二个动机是帮助将非DB2临时表转换为DB2临时表。

Class enrollment , where each student has all of the course schedule selections , each student having his own bucket in the CGTT .

班级入学，每个学生都有所有的课程安排选择，每个学生都将自己的选择放在CGTT中。

The definition of a CGTT is stored in the catalogs like a regular table , and the CGTT is instantiated on the first use by a connection .

CGTT的定义像常规表一样存储在编目中，当一个连接第一次使用CGTT时对它进行实例化。

The main difference between a DGTT and a CGTT is that the definition of a CGTT is stored persistently in the DB2 catalog .

DGTT与CGTT之间的主要差异在于CGTT的定义是持久存储在DB2目录下的。

If you create a CGTT table using the LIKE clause ( create CGTT like a regular table ), the statement will be successful , but the CGTT will not inherit the constraints of the original table .

如果您使用LIKE语句创建CGTT表（像普通表一样创建CGTT），则该语句会执行成功，但CGTT不会继承原始表的约束。

An online shopping cart , where each online user has a CGTT for their shopping cart that is programmatically created and destroyed for their session and copied to a real table when they buy the goods .

在线购物车应用，会话开始时为每个用户的购物车创建一个CGTT，并在会话结束时销毁它，只要在用户真正购买商品后才会复制到实际的表中。