Method of searching data sequences for data which correspond to a specified search argument

摘要

To search data sequences, which are stored in a data storage arrangement (SPA), for a specified search argument, a processor unit is used, compares the characters of the search argument with the data sequence character by character, and gives a positive result signal for equality or a negative result signal (VE) for inequality. For searching, the processor unit uses a search instruction which consists of a search argument, a first address sequence and a second address sequence. To start with, the first character of the search argument which is stored in the search argument memory (SUA-SP) is compared with the first character of the data sequence, in the comparator circuit (VGS). If the result of this comparison is positive, the address of the next character of the search argument in the search argument memory is taken from the first address sequence, which is stored in a first address memory (ADR-SP1). On the other hand, if the result (VE) of this comparison is negative, the next address for a character of the search argument is taken from the second address memory (ADR-SP2). By appropriate selection of the addresses in the second address memory (ADR-SP2), it is possible that, if the result of the comparison is negative, jumps are only within the character sequence of the search argument rather than within the character sequence of the data sequence. IMAGE