Transaction consistency query support for replicated data from recovery log to external data stores

A computer-implemented method for transaction consistency query support for replicated data from a recovery log to an external data store, comprising operations for:

• populating a replicated transformation table in an external data store with records using entries of a change data table in a database management system, by:
• with sequential publishing, for each of the entries:
• determining whether that entry is a last entry for a transaction by checking a last transaction message indicator;
• and
• in response to determining that the entry is the last entry for the transaction, setting a maximum transaction commit sequence identifier value for the transaction to a sequence identifier of the last entry;
• and
• with parallel publishing, for each of the entries,
• determining whether that entry is the last entry for the transaction by checking the last transaction message indicator;
• and
• in response to determining that the entry is the last entry for the transaction, setting a maximum transaction commit sequence identifier value to a last consecutive applied sequence identifier;
• and
• in response to receiving a query at the external data store,
• retrieving a set of records from the replicated transformation table in the external data store;
• determining whether partial changes have been applied, wherein the partial changes are in records of in-flight transactions that have not committed yet in the external data store;
• in response to determining that the partial changes have been applied,
• removing, from the set of records, the records of the in-flight transactions whose sequence identifier values are larger than the maximum transaction commit sequence identifier value;
• and
• returning, from the set of records, remaining records having transaction consistency;
• and
• in response to determining that the partial changes have not been applied, returning the set of records having transaction consistency.