![]() The standard key of a standard table can be empty. Latest notes:When using the primary table key, note that this key can be the standard key, which can also have unexpected consequences:įor structured row types, the standard key covers all character-like and byte-like components. If this is statically identifiable, the syntax check produces a warning. If the primary table key is used to access a standard table and the key is empty, then the first row of the internal table is deleted. If the USING KEY addition is specified, the table key specified in keyname is used. If the USING KEY addition is not specified, the primary table key is used. If the key fields in wa are empty, no entries are processed. The first row of the internal table found, whose values in the columns of the table key used match those of the corresponding components of wa, is processed. This concerns functional operand positions. What does it do? For wa, a work area compatible to the row type of the internal table must be specified. ![]() Al though the rows to be deleted are found quickly, when updating the primary index a linear search for the entry to be deleted must be carried out.ĪBAP Alternative 1. Latest notes:When deleting a row from a standard table using a secondary key, the entire runtime depends linearly on the number of table rows. When the secondary table key is used, a binary scan is used in the sorted key case and a hash algorithm is used in the hash key case. The hash algorithm is used for hashed tables. ![]() When the primary table key is used, the table categories are accessed as follows: Standard tables are searched in a linear fashion.īinary scans are used for sorted tables. The values can be declared either implicitly in a work area wa behind FROM or by listing the components of the table key explicitly behind TABLE KEY. What does it do? Specifying a Table Key as a Search Key Either the primary table key or a secondary table key can be specified.
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