Internal tables are a way to store variable datasets of a fixed structure in the working memory of ABAP. The data is stored on a row-by-row basis, where each row has the same structure.
Internal tables provide the functionality of dynamic arrays and relieve the programmer of the expenditure of a program-controlled dynamic memory management (see Memory management of deep data objects. Internal tables are preferably used to store and format the content of database tables from within a program. Furthermore, internal tables in connection with structures are the most important means of defining very complex data structures in an ABAP program.
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