Overview of the archecker utility

The archecker utility is useful where portions of a database, a table, a portion of a table, or a set of tables need to be recovered. It is also useful in situations where tables need to be moved across server versions or platforms.

Use archecker utility in the following situations:
  • Restore data

    You can use the archecker utility to restore a specific table or set of tables that have previously been backed up with ON-Bar or ontape. These tables can be restored to a specific point in time. This is useful, for example, to restore a table that has accidentally been dropped.

    The following restrictions, however, limit the functionality of the archecker utility in some table-level restore operations:
    • The archecker utility is not JSON compatible. If you try to use the utility with target tables that contain columns of JSON or BSON (binary JSON) data types, the utility will abort and return an error message. (Besides data-restore contexts, this limitation affects all archecker operations on tables with JSON or BSON columns.)
    • You cannot logically restore a table when restoring smart large objects. Only a physical restore of BLOB or CLOB objects is supported for table-level restore operations using the archecker utility.
    • You cannot restore data from a remote device.
    • You cannot use a shared memory connection when performing a table-level restore.
  • Copy data

    The archecker utility can also be used as a method of copying data. For example, you can move a table from the production system to another system.

    The archecker utility is more efficient than other mechanisms for copying data. Because archecker extracts data as text, it can copy data between platforms or server versions.

  • Migrate data

    You can also use the archecker utility as a migration tool to move a table to other HCL® OneDB® servers.

The archecker utility is designed to recover specific tables or sets of tables. Other situations require that you use different utilities. For example, use ON-Bar or ontape in the following data recovery scenarios:
  • Full system restore
  • Recovery from disk failure

To configure the behavior of the archecker utility, use the archecker configuration file. To define the schema of the data that archecker recovers, use the archecker schema command file. These files are described in the following sections.