Verification for replication products and business continuity is critical and requires independent methods to ensure consistency between databases even while they are actively running. HPE Shadowbase Compare provides prompt data-checking to help auditors accomplish regulatory data compliance and peace of mind that the backup database is correct.
HPE Shadowbase Compare and its Repair function run independently of any replication product, allowing both the source and target databases to remain open for updating. It may be used as part of a customer solution to provide evidence for regulatory data validation compliance.
HPE Shadowbase Compare is a utility that compares two HPE NonStop databases (Enscribe and/or SQL) and reports any discrepancies, which may occur, for example, if either a disaster corrupts one of the databases, or a user misconfigures the application or replication environment. Applications may remain active on both the source and target, even for updating, while the comparison takes place. Shadowbase Compare is particularly useful in business continuity data replication environments.
Shadowbase Compare validates that a target database matches its source, and may be used to help satisfy regulatory and audit requirements for data verification. Since Shadowbase Compare works while any data replication product is replicating between the databases, it can also be used to validate an online business continuity replication configuration. It is designed for comparing like-to-like environments, such as HPE NonStop to HPE NonStop source/target (e.g., for Enscribe-to-Enscribe or SQL-to-SQL business continuity). Shadowbase Compare for SQL works across TCP/IP or Expand connected systems; Shadowbase Compare for Enscribe requires Expand connectivity between the systems.
The HPE Shadowbase Compare utility consists of Shadowbase Compare SQL/MP, Shadowbase Compare SQL/MX, and Shadowbase Compare Enscribe. The basic method of comparison is similar for each utility: the contents of the specified target file or table (or subset key range) is read and compared against the contents of the specified source file or table. In some cases, the data to be compared can be compressed to lessen the network load. The “polarity” of which file or table is the source versus the target can be changed, and a comparison can be re-run if so desired.
Shadowbase Compare produces a summary report of counts of differences as well as optionally a detailed report of the specific differences. One set of files or tables (or key ranges) is compared at a time for each comparison run; although many comparisons can be run in parallel against the same table set, for example using a partition break scheme.
HPE Shadowbase Repair is a feature in the HPE Shadowbase Compare for SQL NonStop Utility to assist wth correcting or repairing SQL/MP or SQL/MX database discrepancies between two tables. This feature works on any two database tables, provided they are both of the same type (MP or MX), and does not require the Shadowbase replication engine.
Shadowbase Repair is also particularly useful in business continuity data replication environments. Shadowbase Repair reads Shadowbase Compare’s table of differences, and repairs the discrepancies when the data do not match.
1. Mismatched data
This situation occurs when the tables being compared in the source and target databases have the same primary keys, but their data values differ. Shadowbase Repair can use the values in either the source or target table row to make the data in both tables consistent (match).
2. Row not found
This situation occurs when a row of data is missing in either the source or the target table. Shadowbase Repair can insert or delete values from either table to make both tables consistent.
The user can automatically and quickly correct these discrepancies with just a few simple commands. The user has full control over selecting which table is considered to be correct (referred to as the source table) and which table is considered incorrect (referred to as the target table).