SQL/MX Glossary

Glossary
HP NonStop SQL/MX Glossary—523732-002
Glossary-26
OUT parameter mode
OUT parameter mode. The mode of a parameter that accepts data from a user-defined
routine (UDR). In an SQLJ program, this mode specifies a host variable or expression
that accepts data from an SQLJ clause. It is the default mode if the host expression is
part of an INTO list or an assignment expression. Contrast with IN parameter mode
and INOUT parameter mode.
outer query. A statement containing a subquery or a subquery containing another
subquery. See also inner query and subquery.
outer reference. A reference from an inner query to a table or view defined in an outer
query. See also inner query and outer query.
outer table. In the evaluation of a join, the table that the executor accesses first.
P
parallel execution. The ability of SQL/MX to execute large queries in parallel, using
multiple CPUs simultaneously.
parallel sort. A sorting process that shortens the elapsed time for sorting large files by
distributing the workload to multiple processors and by using scratch files on multiple
disks.
parameter. A placeholder for an argument, which is a value or reference passed to a
routine, command, or program by the caller. See also SQL parameter.
parent node. A node that sends a distributed transaction to another node to perform work
on it. Contrast with child node.
parser. Performs syntax checks and translates the SQL/MX query into a syntactically
correct query tree.
partition lock. A lock held by a process on all the rows in a partition of a table or in a
nonpartitioned table. Contrast with row lock and table lock.
partitioned object. A table or index that resides on more than one disk volume, possibly on
more than one node.
partitioned parallelism. A feature of SQL/MX that provides the ability to divide the data to
be processed into partitions and work on each partition in parallel.
phantom reads. Reads of different sets of committed values that satisfy the same predicate
at different times. Compare with dirty reads and nonrepeatable reads.
physical file attribute. See file attribute.
pipelined parallelism. An inherent feature of SQL/MX that interconnects all operators by
pipes, with the output of one operator being piped as input to the next operator.