International Business Machines Corporation

Shyh-Yee Wang

Hong Sang Tie

Lee-Chin Hsu Liu

Yun Yu Wang

James Zu-Chia Teng

Christina Marie Lee

Desai Paramesh Sampatrai

Hiromi Masuda

Jack R Shedden

Disclosed is a system, method, and program for searching a list of entries. Each entry is comprised of multiple fields. Each field in the entry may include one of a range of possible values for that field. If search criteria is provided for less than all of the fields, then multiple search keys will be generated such that each generated search key includes a search value for each field. The search value for each field for which there are no provided search criteria comprises one of the possible values for that field. A search operation is executed for each of the generated search keys to determine entries in the list that include field values that match the search values in the search key.

Method, system, and program for searching a list of entries when search criteria is provided for less than all of the fields in an entry

Disclosed is a system, method, and program for joining a multi-column table and at least two satellite tables. Each satellite table is comprised of multiple rows and at least one join column and each multi-column table is comprised of multiple rows and join columns corresponding to the join columns in the satellite tables. A query including predicates is received. A join predicate column comprises the satellite table and multi-column table join column to which at least one query predicate applies. A determination is then made as to whether there is at least one index on the multi-column table including at least one column for one join predicate column. One index is selected. The ordering of the join predicate columns in the selected index is used to determine the join order of the satellite tables and the multi-column table. The satellite tables and multi-column tables are then joined in the determined join order.

Method, system, and program for determining the join ordering of tables in a join query

An integrated DBMS solution to recover primary site database based upon the maintenance of a shadow copy of the primary site's database data and logs at a remote site. Both the primary site DBMS and the remote site DBMS may support write-ahead logging protocol in which log records are written to a log data set before database updates are entered into the remote site storage. The remote site serves at least two functions: as a &ldquo;tracker&rdquo; DBMS and as a &ldquo;take-over&rdquo; DBMS. The tracker function maintains a shadow copy of the primary site's database data sets at the remote site. The multi-phased take-over function uses the shadow copies to update the remote site database data sets and substitutes them for primary site database data sets made unavailable by an unplanned disaster at the primary site.

Database disaster remote site recovery

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Cupertino, CA, United States of America

Shyh-Yee Wang