GDBMS 1.0
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A class which encapsulates a transaction over a hash table. It extends hash_table class. xml files for storage and indexing purposes. More...
A class which encapsulates a transaction over a hash table. It extends hash_table class. xml files for storage and indexing purposes.
The files in a hash_table folder could be found in a tr_twin_ht folder as well. In addition to those files, there is an additional file, used by end_transaction method of this class to properly end a transaction.
Such a file has a name: trans_changed_ids_[table_name].xml, where [table_name] is the name of the relation over which, this transaction is created. Typical structure of such a file is as follow:
<ids> {<id [add="1"] | [upd="1"] | [del="1"] myid="some_id">real_id</id>} </ids>
In the above structure, {} shows that what is inside {} can be repeated and A | B relation shows that either A or B can be present, but not both. some_id stands for the corresponding fake id of the transactional record, real_id stands for the id of the record in the real hash table. What is inside [] is not obligatory.