SQL/MX Glossary

Glossary
HP NonStop SQL/MX Glossary—523732-002
Glossary-37
super ID
super ID. A special user ID defined for each node that has NonStop operating system user
name SUPER.Super and user ID 255, 255. The super ID can act as the owner of any
object or file on the node.
swap file. A disk file used by the system for virtual memory.
SYSKEY. A storage key defined by the system rather than by the user. See also clustering
key.
SYSTEM_DEFAULTS. A user metadata table that contains default settings for options and
other attributes that affect the execution of commands and SQL queries that can be
run through MXCI or within an embedded SQL application.
system-defined transaction. A TMF transaction initiated by SQL/MX either in a program
unit or in a requester, on whose behalf the program unit performs database operations.
Contrast with user-defined transaction. Most DDL and DML statements are
transaction-initiating; the system automatically initiates a transaction when the
statement begins executing. The exceptions include DML statements executing on
nonaudited tables or under read uncommitted access on audited tables.
system metadata (SMD). Definition schemas and system schemas that contain SMD
tables. Contrast with user metadata (UMD).
T
table. A logical representation of data in a database in which a set of records is represented
as a sequence of rows, and the set of fields common to all the records is represented
as a series of columns. The intersection of a row and column represents the data value
of a particular field in a particular record. As a database object, a table defines data in
columns and defines the physical characteristics of the table. Contrast with file.
table lock. A lock held by a process on all the rows in all partitions of a partitioned table.
Contrast with partition lock
and row lock.
table reference. A reference in the FROM clause of a SELECT statement that can be a
table, view, derived table, or joined table, and that determines the contents of an
intermediate result table from which SQL/MX returns the columns you specify in the
select list.
targeting. The ability to alter which set of SQL tables is operated on by an application,
without changing the application’s source code. In SQL/MX this is handled by late
name resolution
. The name can be resolved at runtime or when the application is SQL-
compiled. The application approach is useful for production environments.
timeout. A method used by SQL/MX to alleviate deadlocks. If a process cannot acquire a
lock within a given period, the SQL/MX system rejects the lock request and returns a
timeout error.