Stores the global variable in the dataarea for the test engine, which allows access from different tests and different schedule user groups.
将这个全局变量保存到测试引擎的数据区域，这样允许不同的测试和不同调度的用户组进行访问。
2
This is because Oracle uses a lot of virtual memory, particularly with respect to its System GlobalArea (SGA), which is used to cache table data, among other things.
Gets the current file row pointer, stored as an object but used as an integer, from the global variable in the dataarea for the test engine (this will be set up later).