{"id":7635,"date":"2025-08-24T16:52:22","date_gmt":"2025-08-24T11:22:22","guid":{"rendered":"https:\/\/www.sapewmhelp.com\/?question=types-of-internal-tables-in-abap"},"modified":"2025-08-24T16:53:01","modified_gmt":"2025-08-24T11:23:01","slug":"types-of-internal-tables-in-abap","status":"publish","type":"question","link":"https:\/\/www.sapewmhelp.com\/?question=types-of-internal-tables-in-abap","title":{"rendered":"Types of Internal Tables in ABAP"},"content":{"rendered":"

SAP defines three main types<\/strong> of internal tables based on their structure and access method:<\/p>\n

1. Standard Table (STANDARD TABLE<\/code>)<\/strong><\/h5>\n
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    Default type if nothing is specified.<\/p>\n<\/li>\n

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    Entries are stored unsorted<\/strong> (in the order you append them).<\/p>\n<\/li>\n

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    Index-based access<\/strong> (like arrays).<\/p>\n<\/li>\n

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    Duplicate entries allowed<\/strong>.<\/p>\n<\/li>\n

  • \n

    Access time:<\/strong><\/p>\n

      \n
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      By index<\/strong> \u2192 very fast (O(1))<\/p>\n<\/li>\n

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      By key<\/strong> \u2192 linear search (O(n))<\/p>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

      Use Case:<\/strong> Small-to-medium datasets where duplicates are needed, sequential processing.<\/p>\n

       <\/p>\n

      DATA: it_mara TYPE STANDARD TABLE OF mara WITH DEFAULT KEY,
      wa_mara TYPE mara.<\/p>\n

      SELECT * FROM mara INTO TABLE it_mara UP TO 10 ROWS.
      READ TABLE it_mara INTO wa_mara INDEX 5. ” Access by index<\/p>\n

       <\/p>\n

      2. Sorted Table (SORTED TABLE<\/code>)<\/strong><\/h5>\n
        \n
      • \n

        Entries are always stored in a sorted order<\/strong> (by key).<\/p>\n<\/li>\n

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        No need to SORT<\/code> explicitly.<\/p>\n<\/li>\n

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        Unique or non-unique keys<\/strong> possible (depending on definition).<\/p>\n<\/li>\n

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        Binary search<\/strong> used internally for key access.<\/p>\n<\/li>\n

      • \n

        Access time:<\/strong><\/p>\n

          \n
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          By key<\/strong> \u2192 fast (O(log n))<\/p>\n<\/li>\n

        • \n

          By index<\/strong> \u2192 slower than standard<\/p>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n

          Use Case:<\/strong> When you frequently read data by key and want it sorted automatically.<\/p>\n

           <\/p>\n

          DATA: it_mara_sorted TYPE SORTED TABLE OF mara
          WITH UNIQUE KEY matnr.<\/p>\n

          SELECT * FROM mara INTO TABLE it_mara_sorted UP TO 10 ROWS.
          READ TABLE it_mara_sorted WITH TABLE KEY matnr = ‘MAT001’
          INTO DATA(wa_mara).<\/p>\n

           <\/p>\n

          3. Hashed Table (HASHED TABLE<\/code>)<\/strong><\/h5>\n
            \n
          • \n

            Entries are stored in hash algorithm format<\/strong> (like a dictionary).<\/p>\n<\/li>\n

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            Only unique keys allowed<\/strong>.<\/p>\n<\/li>\n

          • \n

            No index access<\/strong> \u2192 can only be accessed via key.<\/p>\n<\/li>\n

          • \n

            Access time:<\/strong> By key \u2192 constant (O(1)) on average.<\/p>\n<\/li>\n

          • \n

            Best for large datasets<\/strong> when you always access by key.<\/p>\n<\/li>\n<\/ul>\n

            Use Case:<\/strong> Fast key-based lookups, like material master lookup by MATNR.<\/p>\n

             <\/p>\n

            DATA: it_mara_hashed TYPE HASHED TABLE OF mara
            WITH UNIQUE KEY matnr.<\/p>\n

            SELECT * FROM mara INTO TABLE it_mara_hashed UP TO 1000 ROWS.
            READ TABLE it_mara_hashed WITH TABLE KEY matnr = ‘MAT001’
            INTO DATA(wa_mara).<\/p>\n

            Summary :\u00a0<\/p>\n\n\n\n\n\n\n\n
            Type<\/th>\nSorted?<\/th>\nDuplicates?<\/th>\nAccess by Index<\/th>\nAccess by Key<\/th>\nPerformance<\/th>\n<\/tr>\n<\/thead>\n
            Standard<\/strong><\/td>\nNo<\/td>\nYes<\/td>\nYes<\/td>\nLinear Search<\/td>\nBest for small, sequential<\/td>\n<\/tr>\n
            Sorted<\/strong><\/td>\nYes<\/td>\nOptional<\/td>\nYes<\/td>\nBinary Search<\/td>\nBest for ordered + key access<\/td>\n<\/tr>\n
            Hashed<\/strong><\/td>\nN\/A<\/td>\nNo<\/td>\nNo<\/td>\nHash Search<\/td>\nBest for large, key-only access<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","question-category":[158],"question_tags":[178,372,189,177],"class_list":["post-7635","question","type-question","status-publish","hentry","question-category-abap","question_tags-abap","question_tags-internal-tables","question_tags-report","question_tags-sap"],"_links":{"self":[{"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=\/wp\/v2\/question\/7635","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=\/wp\/v2\/question"}],"about":[{"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=\/wp\/v2\/types\/question"}],"author":[{"embeddable":true,"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7635"}],"wp:attachment":[{"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7635"}],"wp:term":[{"taxonomy":"question-category","embeddable":true,"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=%2Fwp%2Fv2%2Fquestion-category&post=7635"},{"taxonomy":"question_tags","embeddable":true,"href":"https:\/\/www.sapewmhelp.com\/index.php?rest_route=%2Fwp%2Fv2%2Fquestion_tags&post=7635"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}