Matching transactions in multi-level records

A computer system for identifying matching transactions between two log files, each transaction including one or more programming statements, each programming statement including one or more tokens and an indicator indicating if the programming statement is the end-of-transaction programming statement of the transaction, each log file containing records recording the execution on a computer of the programming statements, each record including a transaction identifier, the tokens, and the end-of-transaction indicator indicating if the record is the end-of-transaction record of the transaction of the corresponding executed programming statement, the computer system comprising:

• one or more processors, one or more computer-readable memories, one or more computer-readable tangible storage devices, and program instructions stored on at least one of the one or more storage devices for execution by at least one of the one or more processors via at least one of the one or more memories, the program instructions comprising:
• program instructions, in response to determining that a least recently read record of a fixed number of sequentially read records from a first log file is not associated with an indication of match, to remove references to the transaction identifier and the programming statement associated with the least recently read record from a first table that includes associations of programming statements to the transaction identifiers to which they are associated, and associations of transaction identifiers to their associated programming statements;
• program instructions, in response to determining that the least recently read record is an end-of-transaction record, to remove references to the transaction identifier associated with the record from the first table;
• program instructions to read a next sequential record from the first log file into the fixed number of sequentially read records;
• program instructions to add information to the first table, based on the transaction identifier and the programming statement information contained in the next sequential record read from the first log file, associating the programming statement to the transaction identifier, and associating the transaction identifier to the programming statement;
• program instructions to read from a second log file the record at a position in the second log file a defined fixed offset of records away from the position in the second log file corresponding to the position in the first log file of the next sequential record read from the first log file;
• program instructions to determine if the record read from the second log file matches a record in the fixed number of sequentially read records;
• program instructions, in response to determining that the record read from the second log file matches a record in the fixed number of sequentially read records, to associate the matched record in the fixed number of sequentially read records with an indication of match, and to add information to a second table that contains associations of transaction identifiers contained in records read from the second log file to transaction identifiers contained in records read from the first log file, based on information contained in the first table;
• program instructions, in response to determining that the record read from the second log file does not match a record in the fixed number of sequentially read records, to remove references to the transaction identifier contained in the record read from the second log file from the second table;
• and
• program instructions, in response to determining that the record read from the second log file matches a record in the fixed number of sequentially read records and that the record read from the second log file is an end-of-transaction record, to associate the matched record in the fixed number of sequentially read records with an indication of match, and to identify a transaction from the first log file that matches a transaction from the second log file based on information contained in the second table.