SQL/MX Glossary

Glossary
HP NonStop SQL/MX Glossary—523732-002
Glossary-25
object schema version (OSV).
object schema version (OSV). The schema version of a database object’s schema. The
version is assigned to the object at create time and changes when the object’s schema
is upgraded or downgraded.
OFV. See object feature version (OFV).
OLT optimization. A method of optimizing online transaction processing performance and
influencing SQL query performance. Some strategies involve simple changes to
system defaults, and others are more complex and involve investigating the query plan
and making appropriate changes to the query or query plan.
online transaction processing (OLTP). A method of processing transactions in which
entered transactions are immediately applied to the database. The information within
the database is readily available to all users through online screens and printed
reports. The transactions are processed while the requester waits, as opposed to
queued or batched transactions, which are processed at a later time.
Online transaction processing can be used for many different kinds of business tasks
such as order processing, inventory control, accounting functions, and banking
operations.
online transaction processing (OLTP) application. An application in which many users
can update data simultaneously, recording the changes in the database as they are
entered. OLTP applications typically use simple queries that require quick response
time against tables containing a mix of read and write requests.
Open Database Connectivity (ODBC). See Microsoft ODBC and NonStop ODBC/MX
association server.
operator. Represents an event in a query plan. Also called a node.
operator tree. A structure that represents operators used in a query plan as nodes, with at
most one parent node for each node in the tree, and with only one root node.
optimization. See query optimization.
optimizer. A component of the SQL compiler that chooses query execution plans for
retrieving data from a database.
ordered stream. An application specifying stream access can retrieve queue entries in the
order of a user-defined clustering key or a system-generated clustering key, the
SYSKEY, if there is no user-defined clustering key. An application can also retrieve
entries in the order of a column value if a secondary index has been created for that
column. Because streams do not return an end-of-data condition, normal sort
operations cannot be used to sort the retrieved entries. Instead, the sort order must be
materialized by the clustering key or a secondary index.
OSV. See object schema version (OSV).