Abstract: A system and method are provided for logically copying data from a source database to a first target database and a second target database. Based on table partition information, the source database is queried to collect partition metadata information for a first set of partitions and a second set of partitions. A first set of the partition metadata information for the first set of partitions and a second set of the partition metadata information for the second set of partitions can be used to create at least one extent chunk for each partition of a table. The source database can be queried, based on a first set of extent chunks and a second set of extent chunks, for a first set of data to be written to the first target database and a second set of data from the source database to be written to the second target database.

Abstract: Techniques are disclosed relating to ensuring data integrity between database objects. A computer system may receive a data integrity request for a first set of database tables. The computer system may generate at least two work items that correspond to respective data cell groups in the first set of database tables. The computer system may then cause a plurality of processes to perform the at least two work items to generate a first plurality of hash values that includes hash values for the respective data cell groups. The first plurality of hash values may be usable to compare with corresponding ones of a second plurality of hash values generated based on corresponding data cell groups in a second set of database tables replicated from the first set of database tables.

Abstract: A system and method are provided for logically copying data from a source database to a first target database and a second target database. Based on table partition information, the source database is queried to collect partition metadata information for a first set of partitions and a second set of partitions. A first set of the partition metadata information for the first set of partitions and a second set of the partition metadata information for the second set of partitions can be used to create at least one extent chunk for each partition of a table. The source database can be queried, based on a first set of extent chunks and a second set of extent chunks, for a first set of data to be written to the first target database and a second set of data from the source database to be written to the second target database.

Abstract: Techniques are disclosed relating to ensuring data integrity between database objects. A computer system may receive a data integrity request for a first set of database tables. The computer system may generate at least two work items that correspond to respective data cell groups in the first set of database tables. The computer system may then cause a plurality of processes to perform the at least two work items to generate a first plurality of hash values that includes hash values for the respective data cell groups. The first plurality of hash values may be usable to compare with corresponding ones of a second plurality of hash values generated based on corresponding data cell groups in a second set of database tables replicated from the first set of database tables.

Abstract: A system and method are provided for logically copying data from a source database to a first target database and a second target database. Based on table partition information, the source database is queried to collect partition metadata information for a first set of partitions and a second set of partitions. A first set of the partition metadata information for the first set of partitions and a second set of the partition metadata information for the second set of partitions can be used to create at least one extent chunk for each partition of a table. The source database can be queried, based on a first set of extent chunks and a second set of extent chunks, for a first set of data to be written to the first target database and a second set of data from the source database to be written to the second target database.

Abstract: An online system performs upgrades of replicated databases. The online system stores data in a primary site and a secondary site. The primary site comprising databases used to process client requests and a secondary site comprising databases used as standby. The online system upgrades databases of both sites by upgrading the secondary site, switching client requests to the secondary site while using the databases of primary site as standby databases. The online system then upgrades the primary site. The process allows the online system to upgrade databases with small down time.