Compare processing using replication log-injected compare records in a replication environment

A computer system comprising:

• a memory;
• and
• a processor in communication with the memory, wherein the computer system is configured to perform a method comprising:
• receiving, by a target system of a replication environment, compare records from a source system of the replication environment, wherein a source datastore of the source system is in a replication relationship with a target datastore of the target system, in which changes to the source datastore are replicated to the target system for application to the target datastore, wherein each compare record of the compare records corresponds to a respective source object, of the source datastore, having source data therein, and the compare record is built by reading the source data of the respective source object of the source database and including in the compare record the read source data of the respective source object, wherein the source data read from a plurality of source objects for which a plurality of the compare records are built is the same as data already stored in corresponding target objects of the target datastore, and wherein the compare records are received in one or more compare transactions to be performed by the target system for determining, for each compare record of the compare records, whether data of the target datastore is consistent with the source data, as provided in the compare record, of the respective source object;
• and
• commencing compare processing to perform the one or more compare transactions by an apply process of the target system, wherein the compare processing comprises:
• processing a compare record of the received compare records, the processing the compare record comprising:
• identifying a selected source object identified by the compare record;
• attempting to locate and read a corresponding target object of the target datastore and obtain target data therefrom;
• and
• further processing the compare record based on whether the corresponding target object is located and read by the attempting;
• and
• processing each of the received compare records, wherein processing each of the received compare records identifies target objects existing in the target datastore that were not indicated by the received compare records as existing in the source datastore;
• and
• providing to the source system an indication of the identified target objects existing in the target datastore that were not indicated by the received compare records, to facilitate a review and determination by the source system of which, if any, of the identified target objects do not exist in the source datastore and are to be deleted at the target;
• based on the review and determination by the source system, receiving, from the source system, in response to providing the indication, and in the form of one or more logged records to be processed by the apply process, indications of which target objects, of the identified target objects existing in the target datastore, are to be deleted at the target;
• and
• deleting from the target datastore the target objects that are to be deleted.

A computer program product comprising:

• a computer readable storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising:
• receiving, by a target system of a replication environment, compare records from a source system of the replication environment, wherein a source datastore of the source system is in a replication relationship with a target datastore of the target system, in which changes to the source datastore are replicated to the target system for application to the target datastore, wherein each compare record of the compare records corresponds to a respective source object, of the source datastore, having source data therein, and the compare record is built by reading the source data of the respective source object of the source database and including in the compare record the read source data of the respective source object, wherein the source data read from a plurality of source objects for which a plurality of the compare records are built is the same as data already stored in corresponding target objects of the target datastore, and wherein the compare records are received in one or more compare transactions to be performed by the target system for determining, for each compare record of the compare records, whether data of the target datastore is consistent with the source data, as provided in the compare record, of the respective source object;
• and
• commencing compare processing to perform the one or more compare transactions by an apply process of the target system, wherein the compare processing comprises:
• processing a compare record of the received compare records, the processing the compare record comprising:
• identifying a selected source object identified by the compare record;
• attempting to locate and read a corresponding target object of the target datastore and obtain target data therefrom;
• and
• further processing the compare record based on whether the corresponding target object is located and read by the attempting;
• and
• processing each of the received compare records, wherein processing each of the received compare records identifies target objects existing in the target datastore that were not indicated by the received compare records as existing in the source datastore;
• and
• providing to the source system an indication of the identified target objects existing in the target datastore that were not indicated by the received comp are records, to facilitate a review and determination by the source system of which, if any, of the identified target objects do not exist in the source datastore and are to be deleted at the target;
• based on the review and determination by the source system, receiving, from the source system, in response to providing the indication, and in the form of one or more logged records to be processed by the apply process, indications of which target objects, of the identified target objects existing in the target datastore, are to be deleted at the target;
• and
• deleting from the target datastore the target objects that are to be deleted.