The index = clauseΒΆ
The index = clause is used in conjunction with a file access command to specify a secondary index which is to be used to access the file. Secondary indexes are set up by the ddeditor program and dynamically maintained by Sculptor. A secondary index has a different key field or fields from that of the main file index. This enables the record to be accessed by different data, and for different search sequences to be used.
The index = clause is omitted if the main file index is to be used.
The access sequence for each index is independent, both of other indexes and of the main file index. If a record is read from the main file, or if a file update command is executed, the file position of the secondary indexes is not changed unless the sync_indexes command is used.
An index = clause may be used in conjunction with a key = clause.
The commands which may take an index = clause are:
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