The data type of an internal table is specified by the following three types:
=>Line Type— The internal table has line type that can be of any data type. Usually, the data type of internal table is structure. In an internal table, each element of structure is a column. It can be also another internal table.
=> Key-- The key indentifies rows of the table. There are two types of keys available for internal tables that are the standard key and the user defined key. The key can be specified either as UNIQUE or NON-UNIQUE. Internal table that contains a unique key cannot have duplicate entries.
=> Table-- The table type specifies how ABAP is accessing the individual table entries. There are three types of internal tables—standard table, sorted table, and hashed table. Standard table contains an internal linear index and a non-unique key. Sorted table also contains an internal index. Table index or key is used by the system to access the entries. Hashed table is accessed only through key.
It does not have any linear index.
=>Line Type— The internal table has line type that can be of any data type. Usually, the data type of internal table is structure. In an internal table, each element of structure is a column. It can be also another internal table.
=> Key-- The key indentifies rows of the table. There are two types of keys available for internal tables that are the standard key and the user defined key. The key can be specified either as UNIQUE or NON-UNIQUE. Internal table that contains a unique key cannot have duplicate entries.
=> Table-- The table type specifies how ABAP is accessing the individual table entries. There are three types of internal tables—standard table, sorted table, and hashed table. Standard table contains an internal linear index and a non-unique key. Sorted table also contains an internal index. Table index or key is used by the system to access the entries. Hashed table is accessed only through key.
It does not have any linear index.