Compaq NonStop SQL/MP Glossary Abstract This manual describes the SQL database terminology used in the Compaq NonStop™ SQL/MP documentation library Product Version NonStop SQL/MP G07 Supported Releases This manual supports G06.13 and all subsequent releases until otherwise indicated in a new edition.
Document History Part Number Product Version Published 119358 NonStop SQL/MP D31 February 1996 429832.001 NonStop SQL/MPG07 July 2001 Ordering Information For manual ordering information: domestic U.S. customers, call 1-800-243-6886; international customers, contact your local sales representative. Document Disclaimer Information contained in a manual is subject to change without notice. Please check with your authorized representative to make sure you have the most recent information.
Compaq NonStop™ SQL/MP Glossary What’s New in This Manual iii Manual Information iii New and Changed Information iii About This Manual v Audience v Related Manuals v Your Comments Invited vi Glossary Figures Figure i.
Contents Compaq NonStop™ SQL/MP Glossary—429832-001 ii
What’s New in This Manual Manual Information Compaq NonStop SQL/MP Glossary Abstract This manual describes the SQL database terminology used in the Compaq NonStop™ SQL/MP documentation library Product Version NonStop SQL/MP G07 Supported Releases This manual supports G06.13 and all subsequent releases until otherwise indicated in a new edition. Part Number Published 429832-001 July 2001 Document History Part Number Product Version Published 119358 NonStop SQL/MP D31 February 1996 429832.
What’s New in This Manual New and Changed Information Compaq NonStop™ SQL/MP Glossary—429832-001 iv
About This Manual Compaq NonStop™ SQL/MP is the Compaq implementation of a relational database management system that uses the industry-standard Structured Query Language (SQL) to define and manipulate data. This manual describes the SQL database terminology used in the NonStop™ SQL/MP documentation library. Audience All SQL/MP users can benefit from this manual. Related Manuals This manual is part of the NonStop SQL/MP™ library of manuals, as shown in Figure i.
Your Comments Invited About This Manual Figure i.
Glossary absolute pathname. In the Compaq NonStop Kernel Open System Services (OSS) environment, a pathname that begins with a slash (/) character and is resolved beginning with the root directory. accelerate. To use the Accelerator program to generate an accelerated object file. accelerated object code. The RISC instructions that result from processing a TNS object file with the Accelerator. accelerated object file. The object file that results from processing a TNS object file with the Accelerator.
approximate numeric type Glossary approximate numeric type. A numeric data type that is an approximation of a real number and consists of two parts: a mantissa and an exponent. The mantissa is a signed numeric value, and the exponent is a signed integer that specifies the magnitude of the mantissa. The SQL approximate numeric types are FLOAT, REAL, and DOUBLE PRECISION. Contrast with exact numeric type. attribute.
browse access Glossary browse access. An access option for transaction consistency that gives users immediate access to data when a transaction in progress might be changing the data. With browse access, a process does not acquire a lock on the data it accesses and does not test for existing locks before reading data. Browse access can be specified only for reading data. Of the access options, browse access provides the lowest consistency but the highest concurrency.
character set Glossary character set. A set of characters that can be associated with columns, literals, host variables, parameters, functions, and expressions that have a character data type. NonStop SQL/MP supports the ASCII character set, ISO 8859/1 through ISO 8859/9 character sets, Kanji character set, and KSC5601 character set. See also system default national character set and UNKNOWN character set. clustering key.
command interpreter Glossary command interpreter. A process that manages interactive communication between the user and the operating system, such as a TACL process. compilation unit. All the data declarations and units of code specified for processing by one run of a host language compiler. concurrency. Access to the same data at the same time by two or more processes. concurrent access. The ability of two or more processes to gain access to the same data at the same time.
Data Build product Glossary Data Build product. A Compaq product for converting other vendors’ data to Compaq database structures. data consistency. The condition of a database when data values agree with one another according to user-defined criteria. Consistency is one aspect of data integrity. Data Control Language. See DCL (Data Control Language). data control statement. See DCL statement. Data Definition Language. See DDL (Data Definition Language). data definition statement. See DDL statement.
data-type attribute Glossary data-type attribute. A format, character set, collation, or coercibility attribute associated with a data type for a column, expression, function, host variable, literal, or parameter. datetime qualifier. See range of DATETIME fields. date-time data type. The DATETIME, DATE, TIME, or TIMESTAMP data type. DATE, TIME, and TIMESTAMP are predefined subsets of DATETIME.
DEFINE name Glossary DEFINE name. An identifier that can be used in place of an actual subvolume or file name in an SQL statement to identify a catalog, table, view, index, collation, file, or partition; the identifier starts with an equal sign. NonStop SQL/MP replaces the logical DEFINE name with the actual name when compiling or recompiling the statement. See also DEFINE. definitional integrity.
double-byte character set Glossary double-byte character set. A character set consisting of characters that require two bytes each for storage. double-byte column. A column that has an associated double-byte character set. DP2. See disk process. DSL (Data Status Language). The set of data status statements within the SQL language. DSL statement. A statement that retrieves status information about the version of a database. Contrast with DCL statement, DDL statement, and DML statement. dynamic SQL.
exclusive access Glossary exclusive access. See repeatable access. exclusive lock. A lock exclusion mode in which only the holder of the lock can access the locked data, except with browse access. Contrast with shared lock. execution characteristics. The characteristics of an SQL statement’s execution plan that have no effect on the statement’s semantics. Examples include a plan’s performance, node autonomy, resource use, and locking strategy. execution plan.
fallback node Glossary fallback node. A node on which the NonStop SQL/MP system software has an older version than an object, catalog, or program on the same node. field. A portion of a record reserved for a specific item of information. In relational terms, each column of a table represents one field. In a date-time or INTERVAL column value, a DATETIME field or INTERVAL field, such as HOUR, is a specific part of the value. file.
fileset Glossary fileset. A specification of one or more files used in SQLCI utility commands, optionally using wild-card characters to define name patterns. (Note that this is not the same as the Open System Services (OSS) definition of fileset.) first key. The primary-key value or clustering-key value allowed for the first row in a partition. Whether the value in each key column is high or low depends on the ascending or descending collating sequence defined for the column.
Guardian operating system Glossary Guardian operating system. An environment available for interactive or programmatic use with the Compaq NonStop Kernel Operating System. Processes that run in the Guardian environment use the Guardian system procedure calls as their application program interface; interactive users of the Guardian environment use the Compaq Tandem Advanced Command Language (TACL) or another Compaq product’s command interpreter. Contrast with Open System Services (OSS). hash join.
hybrid hash join Glossary hybrid hash join. A hash join method that retains as much as possible of the inner table in memory but divides rows of both inner and outer tables into clusters that reside on disk and can be processed in memory. Ordering is not preserved. See also simple hash join. implicit correlation name. A table or view name for which no correlation name is specified in the FROM clause of a SELECT statement. Contrast with explicit correlation name. index.
invalid object Glossary invalid object. A table, view, index, or collation that is unusable because its file label is not consistent with its catalog entries, or because the object contains data that does not satisfy constraints on the object or that is inconsistent with a related object. invalid program. A program that is marked as SQL invalid because an invalidating operation occurred to at least one of its execution plans.
key-sequenced merge join Glossary key-sequenced merge join. A join method that can apply a merge join to key-sequenced tables without doing a sort or using a temporary file. The method involves an inner table and either a single outer table or a composite table with matching order. key-sequenced table.
lock holder Glossary lock holder. The process that acquires an exclusive or shared lock on data, sometimes called lock owner. For audited tables, the lock holder is identified by a transaction ID. lockable unit. The amount of data that can be protected by a single lock. Tables, partitions of tables, subsets of rows, and single rows are lockable units. See also lock granularity. low PIN. A process identification number (PIN) in the range 0 through 255. MDAM (MultiDimensional Access Method).
NATIONAL CHARACTER data type Glossary NATIONAL CHARACTER data type. See NCHAR (NATIONAL CHARACTER data type). national character string literal. A literal that has the NATIONAL CHARACTER data type. NCHAR (NATIONAL CHARACTER data type). A data type whose values are composed of the characters in the system default national character set. nested join.
NonStop SQL/MP conversational interface Glossary All NonStop SQL/MP components on the same node must have the same software version. NonStop SQL/MP conversational interface. See SQLCI (SQL conversational interface). NonStop SQL/MP database. A database created by NonStop SQL/MP software.
older version Glossary older version. A version that has a lower version number than another version. OLTP (online transaction processing) application. An application in which many users can update data simultaneously, recording the changes in the database as they are entered. online dump. A copy of an audited database file written to disk or tape when a TMF DUMP FILES command is issued.
packed record format Glossary packed record format. A layout of all values in a row in the form of a record in which all blank padding at the end of the values of a variable-length character data type and all blank padding preceding word-aligned values have been removed. Contrast with exploded record format. page footing. One or more lines of text that appear at the end of each report page. page title. A title that appears at the top of each report page. PAID (process accessor ID).
physical file attribute Glossary physical file attribute. See file attribute. physical primary key. The unique value that identifies the rows in a table and determines the order in which rows are stored in a file. Within a table, each row’s primary key value must be unique. The physical primary key is derived from a table’s definition. Contrast with index. See also clustering key, index, primary key, system-defined primary key, and user-defined primary key. PIN (process identification number).
process file segment (PFS) Glossary process file segment (PFS). A proprietary extended data segment, defined by the file system, that contains the user’s process context and the working storage for the file system. process identification number. See PIN (process identification number). process name. An operating system name that can be assigned to a process when the process is created. A process name uniquely identifies a process or process pair on a node. program catalog version (PCV).
range of DATETIME fields Glossary range of DATETIME fields. The subset of fields that compose a value of type DATETIME, DATE, TIME, or TIMESTAMP; also called a datetime qualifier. Some sample ranges are YEAR TO DAY, HOUR TO SECOND, and MONTH TO MINUTE. range of INTERVAL fields. The subset of fields that compose a value of type INTERVAL. The range can include either year-month or day-time fields, but not both. Some sample ranges are YEAR, DAY TO HOUR, and MINUTE TO SECOND. Real Sequential Block Buffering.
report clause Glossary report clause. An element of a print item that specifies such operations as spacing and conditional printing of information. report column. A column in the output from a SELECT statement. report command. One of a set of commands that formats a particular query as a report. Report commands include the specification of the content and format of detail lines, the grouping of detail lines, and the report title. report footing.
SCI (SQL compiler interface) Glossary SCI (SQL compiler interface). .The NonStop SQL/MP interface to the host-language compilers. search condition. A predicate or compound predicate that defines the criteria for selecting data or for including data in a table or view. security string. The 4-character string of security codes that determines whether a user has read, write, execute, or purge authority for an object. select list.
similarity information Glossary similarity information. Information about an SQL object that the SQL compiler stores in the program file. During subsequent recompilations, NonStop SQL/MP can use the information to perform a similarity check. See also similarity check. simple fileset list. A list of one or more filesets. Contrast with qualified fileset list. simple hash join. A hash join method in which the inner table is read into a memory-resident hash table. The order of the outer table is preserved.
SQL conversational interface Glossary SQL conversational interface. See SQLCI (SQL conversational interface). SQL data structure. Any of three data structures that an SQL program can include: SQLCA (SQL communications area), SQLDA (SQL descriptor area), and SQLSA (SQL statistics area). SQL descriptor area. See SQLDA (SQL descriptor area). SQL executor. See executor. SQL file system. See file system. SQL identifier.
SQL statistics area Glossary SQL statistics area. See SQLSA (SQL statistics area). SQL string. A character string embedded in a host program, or entered dynamically at run time, that consists of a single SQL statement or a single preprocessor or compiler directive. When embedded, an SQL string begins with the keywords EXEC SQL. SQL system catalog format version. See system catalog format version. SQL system catalog version. See system catalog version. SQL system version. See software version.
string literal Glossary string literal. Data composed of single-byte or double-byte characters. A string literal has the data type CHARACTER or NATIONAL CHARACTER and can have an associated character set. Structured Query Language. See SQL (Structured Query Language). style option. One of a set of options that control the default elements of a report. Style options include specification of date and time formats, the underline character, the decimal character, and headings.
system-defined primary key Glossary system-defined primary key. The primary key that identifies each row in an entrysequenced or relative table or in a key-sequenced table for which there is no other userdefined key. The column name of the system-defined primary key for a table is SYSKEY. Other column names can represent SYSKEY for views. Contrast with userdefined primary key. See also clustering key, primary key, and SYSKEY column. table.
TNS Glossary error occurs while a transaction is in progress, the TMF subsystem backs out whatever partial changes were made to the database, leaving it in a consistent state. TNS. See Tandem NonStop Series (TNS). TNS/R. See Tandem NonStop Series/RISC (TNS/R). transaction. A series of changes that transform a database from one consistent state to another. See also TMF transaction. transaction backout.
view Glossary view. A table that has a logical definition and a file label but contains no data. A view is derived by projecting a subset of the columns, restricting a subset of the rows, or both from one or more base tables or other views. A view is either a protection view or a shorthand view. Virtual Sequential Block Buffering. See VSBB (Virtual Sequential Block Buffering). volume recovery. A TMF feature for restoring tables or disk files to their most recent consistent state.
ZZ, ZQ, or ZYQ file Glossary Compaq NonStop™ SQL/MP Glossary—429832-001 Glossary -34
