abap memory?

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report zxy_0002 .

data: it001 type table of t001 with header line.

select * into table it001 from t001.

export it001 = it001 to memory id 'ZXY_TEST'.

clear it001. refresh it001.

import it001 = it001 from memory id 'ZXY_TEST'.

loop at it001.

write:/ it001-bukrs, it001-butxt.

endloop.

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Hi abap experts,

I have gone through above small program abou abap memory from some study material.

i need few more explanation about memory id 'ZXY_TEST' where it locates?

how to see whether the memory id ZXY_TEST has the data or not?