Glossary

Adaptive Server Enterprise

A server in Sybase’s client/server architecture. Adaptive Server manages multiple databases and multiple users, keeps track of the actual location of data on disks, maintains mapping of logical data description to physical data storage, and maintains data and procedure caches in memory.

NotePrior to version 11.5, Adaptive Server Enterprise was known as SQL Server.

array

A structure composed of multiple identical variables that can be individually addressed.

array binding

The process of binding a result column to an array variable. At fetch time, multiple rows’ worth of the column are copied into the variable.

batch

A group of commands or statements.

A Client-Library command batch is one or more Client-Library commands terminated by an application’s call to ct_send. For example, an application can batch together commands to declare, set rows for, and open a cursor.

A Transact-SQL statement batch is one or more Transact-SQL statements submitted to Adaptive Server by means of a single Client-Library command or Embedded SQL statement.

browse mode

A method that DB-Library and Client-Library applications can use to browse through database rows, updating their values one row at a time. Cursors provide similar functionality and are generally more portable and flexible.

bulk copy

A utility for copying data in and out of databases. Also called bcp.

callback event

In Open Client and Open Server, an occurrence that triggers a callback routine.

callback routine

A routine that Open Client or Open Server calls in response to a triggering event, known as a callback event.

capabilities

In terms of client/server connections, determine the types of client requests and server responses permitted for that connection.

character set

A set of specific (usually standardized) characters with an encoding scheme that uniquely defines each character. ASCII and ISO 8859-1 (Latin 1) are two common character sets.

character set conversion

Changing the encoding scheme of a set of characters on the way into or out of a server. Conversion is used when a server and a client communicating with it use different character sets. For example, if Adaptive Server uses ISO 8859-1 and a client uses Code Page 850, character set conversion must be turned on so that both server and client interpret the data passing back and forth in the same way.

client

In client/server systems, the part of the system that sends requests to servers and processes the results of those requests.

Client-Library

Part of Open Client, a collection of routines used to write client applications. Client-Library accommodates cursors and other advanced features in the Sybase product line.

code set

See character set.

collating sequence

See sort order.

command

In Client-Library, a command is a server request initiated by an application’s call to ct_command, ct_dynamic, or ct_cursor and terminated by the application’s call to ct_send.

command structure

A hidden Client-Library structure (CS_COMMAND) that Client-Library applications use to send commands and process results.

connection structure

A hidden Client-Library structure (CS_CONNECTION) that defines a client/server connection within a context.

context structure

A CS-Library hidden structure (CS_CONTEXT) that defines an application “context,” or operating environment, within a Client-Library or Open Server application. The CS-Library routines cs_ctx_alloc and cs_ctx_drop allocate and drop a context structure, respectively.

conversion

See character set conversion.

CS-Library

Included with both the Open Client and Open Server products, a collection of utility routines that are useful to both Client-Library and Server-Library applications.

current row

With respect to cursors, is the row to which a cursor points. A fetch against a cursor retrieves the current row.

cursor

A symbolic name that is associated with a SQL statement.

In Embedded SQL, a cursor is a data selector that passes multiple rows of data to the host program, one row at a time.

database

A set of related data tables and other database objects that are organized to serve a specific purpose.

datatype

A defining attribute that describes the values and operations that are legal for a variable.

DB-Library

Part of Open Client, a collection of routines for use in writing client applications.

deadlock

A situation that arises when two users, each having a lock on one piece of data, attempt to acquire a lock on the other’s piece of data. Adaptive Server detects deadlocks and resolves them by killing one user’s process.

default

Describes the value, option, or behavior that Open Client/Server products use when none is explicitly specified.

default database

The database that a user gets by default when he or she logs in to a database server.

default language

1. The language that Open Client/Server products use when an application does no explicit localization. The default language is determined by the “default” entry in the locales file.

2. The language that Adaptive Server uses for messages and prompts when a user has not explicitly chosen a language.

Dynamic SQL

A type of SQL that allows an Embedded SQL or Client-Library application to execute SQL statements containing variables whose values are determined at runtime.

error message

A message that an Open Client/Server product issues when it detects an error condition.

event

An occurrence that prompts an Open Server application to take certain actions. Client commands and certain commands within Open Server application code can trigger events. When an event occurs, Open Server calls either the appropriate event-handling routine in the application code or the appropriate default event handler.

event handler

In Open Server, a routine that processes an event. An Open Server application can use the default handlers Open Server provides or can install custom event handlers.

exposed structure

A structure whose internals are exposed to Open Client/Server programmers. Open Client/Server programmers can declare, manipulate, and de-allocate exposed structures directly. The CS_DATAFMT structure is an example of an exposed structure.

extended transaction

In Embedded SQL, a transaction composed of multiple Embedded SQL statements.

FIPS

Federal Information Processing Standards. If FIPS flagging is enabled, Adaptive Server or the Embedded SQL precompiler issue warnings when a non-standard extension to a SQL statement is encountered.

gateway

An application that acts as an intermediary for clients and servers that cannot communicate directly. Acting as both client and server, a gateway application passes requests from a client to a server and returns results from the server to the client.

hidden structure

A structure whose internals are hidden from Open Client/Server programmers. Open Client/Server programmers must use Open Client/Server routines to allocate, manipulate, and deallocate hidden structures. The CS_CONTEXT structure is an example of a hidden structure.

host language

The programming language in which an application is written.

host program

In Embedded SQL, is the application program that contains the Embedded SQL code.

host variable

In Embedded SQL, a variable that enables data transfer between Adaptive Server and the application program. See also indicator variable, input variable, output variable, result variable, and status variable.

indicator variable

A variable whose value indicates special conditions about another variable’s value or about fetched data.

When used with an Embedded SQL host variable, an indicator variable indicates when a database value is null.

input variable

A variable that is used to pass information to a routine, a stored procedure, or Adaptive Server.

interfaces file

A file that maps server names to transport addresses. When a client application calls ct_connect or dbopen to connect to a server, Client-Library or DB-Library searches the interfaces file for the server’s address. Note that not all platforms use the interfaces file. On these platforms, an alternate mechanism directs clients to server addresses.

isql script file

In Embedded SQL, one of the three files the precompiler can generate. An isql script file contains precompiler-generated stored procedures, which are written in Transact-SQL.

key

A subset of row data that uniquely identifies a row. Key data uniquely describes the current row in an open cursor.

keyword

A word or phrase that is reserved for exclusive use in Transact-SQL or Embedded SQL. Also called a reserved word.

listing file

In Embedded SQL, one of the three files the precompiler can generate. A listing file contains the input file’s source statements and informational, warning, and error messages.

locale name

A character string that represents a language/character set pair. Locale names are listed in the locales file. Sybase predefines some locale names, but a system administrator can define additional locale names and add them to the locales file.

locale structure

A CS-Library hidden structure (CS_LOCALE) that defines custom localization values for a Client-Library or Open Server application. An application can use a CS_LOCALE to define the language, character set, datepart ordering, and sort order it will use. The CS-Library routines cs_loc_alloc and cs_loc_drop allocate and drop a locale structure.

locales file

A file that maps locale names to language/character set pairs. Open Client/Server products search the locales file when loading localization information.

localization

The process of setting up an application to run in a particular national language environment. An application that is localized typically generates messages in a local language and character set and uses local datetime formats.

login name

The name a user uses to log in to a server. An Adaptive Server login name is valid if Adaptive Server has an entry for that user in the system table syslogins.

message number

A number that uniquely identifies an error message.

message queue

In Open Server, a linked list of message pointers through which threads communicate. Threads can write messages into and read messages from the queue.

multi-byte character set

A character set that includes characters encoded using more than 1 byte. EUC JIS and Shift-JIS are examples of multibyte character sets.

mutex

A mutual exclusion semaphore. This is a logical object that an Open Server application uses to ensure exclusive access to a shared object.

null

Having no explicitly assigned value. NULL is not equivalent to zero, or to blank. A value of NULL is not considered to be greater than, less than, or equivalent to any other value, including another value of NULL.

Open Server

A Sybase product that provides tools and interfaces for creating custom servers.

Open Server application

A custom server constructed with Open Server.

output variable

In Embedded SQL, a variable that passes data from a stored procedure to an application program.

parameter

1. A variable that is used to pass data to and retrieve data from a routine.

2. An argument to a stored procedure.

passthrough mode

Tabular Data Stream (TDS) packets between a client and a remote data source without unpacking the packets’ contents.

property

A named value stored in a structure. Context, connection, thread, and command structures have properties. A structure’s properties determine how it behaves.

query

1. A data retrieval request; usually a select statement.

2. Any SQL statement that manipulates data.

registered procedure

In Open Server, a collection of C statements stored under a name. Open Server-supplied registered procedures are called system registered procedures.

remote procedure call (RPC)

1. One of two ways in which a client application can execute an Adaptive Server stored procedure. (The other is with a Transact-SQL execute statement.) A Client-Library application initiates a remote procedure call command by calling ct_command. A DB-Library application initiates a remote procedure call command by calling dbrpcinit.

2. A type of request a client can make of an Open Server application. In response, Open Server either executes the corresponding registered procedure or calls the Open Server application’s RPC event handler.

3. A stored procedure executed on a server that is different from the server to which the user is connected.

result variable

In Embedded SQL, a variable which receives the results of a select or fetch statement.

server

In client/server systems, the server is the part of the system that processes client requests and returns results to clients.

Server-Library

A collection of routines for use in writing Open Server applications.

sort order

Used to determine the order in which character data is sorted. Also called collating sequence.

SQLCA

1. In an Embedded SQL application, a structure that provides a communication path between Adaptive Server and the application program. After executing each SQL statement, Adaptive Server stores return codes in SQLCA.

2. In a Client-Library application, a structure that the application can use to retrieve Client-Library and server error and informational messages.

SQLCODE

1. In an Embedded SQL application, a structure that provides a communication path between Adaptive Server and the application program. After executing each SQL statement, Adaptive Server stores return codes in SQLCODE. A SQLCODE can exist independently or as a variable within a SQLCA structure.

2. In a Client-Library application, a structure that the application can use to retrieve Client-Library and server error and informational message codes.

SQL Server

See Adaptive Server Enterprise.

statement

In Transact-SQL or Embedded SQL, an instruction that begins with a keyword. The keyword names the basic operation or command to be performed.

status variable

In Embedded SQL, a variable that receives the return status value of a stored procedure, thereby indicating the procedure’s success of failure.

stored procedure

In Adaptive Server, a collection of SQL statements and optional control-of-flow statements stored under a name. Adaptive Server-supplied stored procedures are called system procedures.

System Administrator

The user in charge of Adaptive Server system administration, including creating user accounts, assigning permissions, and creating new databases. On Adaptive Server, the System Administrator’s login name is "sa."

system descriptor

In Embedded SQL, an area of memory that holds a description of variables used in Dynamic SQL statements.

system procedures

Stored procedures that Adaptive Server supplies for use in system administration. These procedures are provided as shortcuts for retrieving information from system tables, or as mechanisms for accomplishing database administration and other tasks that involve updating system tables.

system registered procedures

Internal registered procedures that Open Server supplies for registered procedure notification and status monitoring.

target file

In Embedded SQL, one of three files the precompiler can generate. A target file is similar to the original input file, except that all SQL statements are converted to Client-Library function calls.

TDS

(Tabular Data Stream) An application-level protocol that Sybase clients and servers use to communicate. It describes commands and results.

thread

A path of execution through Open Server application and library code and the path’s associated stack space, state information, and event handlers.

Transact-SQL

An enhanced version of the database language SQL. Applications can use Transact-SQL to communicate with Sybase Adaptive Server.

transaction

One or more server commands that are treated as a single unit for the purposes of backup and recovery. Commands within a transaction are committed as a group; that is, either all of them are committed or all of them are rolled back.

transaction mode

Refers to the manner in which Adaptive Server manages transactions. Adaptive Server supports two transaction modes: Transact-SQL mode (also called “unchained transactions”) and ANSI mode (also called “chained transactions”).

user name

See login name.